<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <link:roleRef roleURI="http://www.nanostring.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPolicies" xlink:href="nstg-20180930.xsd#BasisOfPresentationAndSummaryOfSignificantAccountingPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" xlink:href="nstg-20180930.xsd#BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesPolicies" xlink:href="nstg-20180930.xsd#BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/CollaborationAgreements" xlink:href="nstg-20180930.xsd#CollaborationAgreements" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/CollaborationAgreementsAdditionalInformationDetail" xlink:href="nstg-20180930.xsd#CollaborationAgreementsAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/CommitmentsAndContingencies" xlink:href="nstg-20180930.xsd#CommitmentsAndContingencies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/ConcentrationOfRisks" xlink:href="nstg-20180930.xsd#ConcentrationOfRisks" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/ConcentrationOfRisksAdditionalInformationDetail" xlink:href="nstg-20180930.xsd#ConcentrationOfRisksAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/CondensedConsolidatedBalanceSheets" xlink:href="nstg-20180930.xsd#CondensedConsolidatedBalanceSheets" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:href="nstg-20180930.xsd#CondensedConsolidatedBalanceSheetsParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/CondensedConsolidatedStatementsOfCashFlows" xlink:href="nstg-20180930.xsd#CondensedConsolidatedStatementsOfCashFlows" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/CondensedConsolidatedStatementsOfComprehensiveLoss" xlink:href="nstg-20180930.xsd#CondensedConsolidatedStatementsOfComprehensiveLoss" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/CondensedConsolidatedStatementsOfOperations" xlink:href="nstg-20180930.xsd#CondensedConsolidatedStatementsOfOperations" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/DescriptionOfBusiness" xlink:href="nstg-20180930.xsd#DescriptionOfBusiness" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/DescriptionOfBusinessAdditionalInformationDetails" xlink:href="nstg-20180930.xsd#DescriptionOfBusinessAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/DocumentAndEntityInformation" xlink:href="nstg-20180930.xsd#DocumentAndEntityInformation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/FairValueMeasurements" xlink:href="nstg-20180930.xsd#FairValueMeasurements" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/FairValueMeasurementsCompanysAvailableForSaleSecuritiesByLevelWithinFairValueHierarchyDetail" xlink:href="nstg-20180930.xsd#FairValueMeasurementsCompanysAvailableForSaleSecuritiesByLevelWithinFairValueHierarchyDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/FairValueMeasurementsTables" xlink:href="nstg-20180930.xsd#FairValueMeasurementsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/InformationAboutGeographicAreas" xlink:href="nstg-20180930.xsd#InformationAboutGeographicAreas" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/InformationAboutGeographicAreasAdditionalInformationDetail" xlink:href="nstg-20180930.xsd#InformationAboutGeographicAreasAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/InformationAboutGeographicAreasClassificationOfRevenueByGeographyDetail" xlink:href="nstg-20180930.xsd#InformationAboutGeographicAreasClassificationOfRevenueByGeographyDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/InformationAboutGeographicAreasTables" xlink:href="nstg-20180930.xsd#InformationAboutGeographicAreasTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/Inventory" xlink:href="nstg-20180930.xsd#Inventory" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/InventoryScheduleOfInventoryDetail" xlink:href="nstg-20180930.xsd#InventoryScheduleOfInventoryDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/InventoryTables" xlink:href="nstg-20180930.xsd#InventoryTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/LongTermDebt" xlink:href="nstg-20180930.xsd#LongTermDebt" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/LongTermDebtAdditionalInformationDetail" xlink:href="nstg-20180930.xsd#LongTermDebtAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/LongTermDebtComponentsOfBorrowingsIncludingCurrentPortionDetail" xlink:href="nstg-20180930.xsd#LongTermDebtComponentsOfBorrowingsIncludingCurrentPortionDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/LongTermDebtScheduledFuturePrincipalPaymentsUnderOutstandingDebtObligationsDetail" xlink:href="nstg-20180930.xsd#LongTermDebtScheduledFuturePrincipalPaymentsUnderOutstandingDebtObligationsDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/LongTermDebtTables" xlink:href="nstg-20180930.xsd#LongTermDebtTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/NetLossPerShare" xlink:href="nstg-20180930.xsd#NetLossPerShare" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/NetLossPerShareSummaryOfSharesUnderlyingOutstandingOptionsAndWarrantsWereExcludedFromComputationOfBasicAndDilutedNetLossPerShareDetail" xlink:href="nstg-20180930.xsd#NetLossPerShareSummaryOfSharesUnderlyingOutstandingOptionsAndWarrantsWereExcludedFromComputationOfBasicAndDilutedNetLossPerShareDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/NetLossPerShareTables" xlink:href="nstg-20180930.xsd#NetLossPerShareTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/RevenueFromContractsWithCustomersNarrativeDetails" xlink:href="nstg-20180930.xsd#RevenueFromContractsWithCustomersNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/RevenueFromContractsWithCustomersNotes" xlink:href="nstg-20180930.xsd#RevenueFromContractsWithCustomersNotes" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/RevenueFromContractsWithCustomersPerformanceObligationsDetails" xlink:href="nstg-20180930.xsd#RevenueFromContractsWithCustomersPerformanceObligationsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/RevenueFromContractsWithCustomersScheduleOfDisaggregatedRevenueDetails" xlink:href="nstg-20180930.xsd#RevenueFromContractsWithCustomersScheduleOfDisaggregatedRevenueDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/RevenueFromContractsWithCustomersScheduleOfImpactOfChangesInAccountingStandardDetails" xlink:href="nstg-20180930.xsd#RevenueFromContractsWithCustomersScheduleOfImpactOfChangesInAccountingStandardDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/RevenueFromContractsWithCustomersTables" xlink:href="nstg-20180930.xsd#RevenueFromContractsWithCustomersTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/ShortTermInvestments" xlink:href="nstg-20180930.xsd#ShortTermInvestments" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/ShortTermInvestmentsAdditionalInformationDetail" xlink:href="nstg-20180930.xsd#ShortTermInvestmentsAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/ShortTermInvestmentsAvailableForSaleSecuritiesDetail" xlink:href="nstg-20180930.xsd#ShortTermInvestmentsAvailableForSaleSecuritiesDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/ShortTermInvestmentsFairValuesOfAvailableForSaleSecuritiesByContractualMaturityDetail" xlink:href="nstg-20180930.xsd#ShortTermInvestmentsFairValuesOfAvailableForSaleSecuritiesByContractualMaturityDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/ShortTermInvestmentsSummaryOfInvestmentsInContinuousLossPositionDetails" xlink:href="nstg-20180930.xsd#ShortTermInvestmentsSummaryOfInvestmentsInContinuousLossPositionDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/ShortTermInvestmentsTables" xlink:href="nstg-20180930.xsd#ShortTermInvestmentsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/SubsequentEvent" xlink:href="nstg-20180930.xsd#SubsequentEvent" xlink:type="simple" />
  <link:roleRef roleURI="http://www.nanostring.com/role/SubsequentEventNarrativeDetails" xlink:href="nstg-20180930.xsd#SubsequentEventNarrativeDetails" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" xlink:type="simple" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPolicies" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="nstg-20180930.xsd#nstg_SignificantAccountingPoliciesLineItems" xlink:label="loc_nstg_SignificantAccountingPoliciesLineItems_CD2700922D73505698A93DD9046DCB6E" xlink:type="locator" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_SignificantAccountingPoliciesTable" xlink:label="loc_nstg_SignificantAccountingPoliciesTable_BD32832D1965193143F73DD904687E62" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_nstg_SignificantAccountingPoliciesLineItems_CD2700922D73505698A93DD9046DCB6E" xlink:to="loc_nstg_SignificantAccountingPoliciesTable_BD32832D1965193143F73DD904687E62" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_DB6947402340F4EAE8323DD90468452B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_nstg_SignificantAccountingPoliciesTable_BD32832D1965193143F73DD904687E62" xlink:to="loc_us-gaap_RangeAxis_DB6947402340F4EAE8323DD90468452B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_E674B3924D61FE74077C3DD9046D07A0_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_DB6947402340F4EAE8323DD90468452B" xlink:to="loc_us-gaap_RangeMember_E674B3924D61FE74077C3DD9046D07A0_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_E674B3924D61FE74077C3DD9046D07A0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_DB6947402340F4EAE8323DD90468452B" xlink:to="loc_us-gaap_RangeMember_E674B3924D61FE74077C3DD9046D07A0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_429FDD031DAAAC9537253DD9046DC764" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_E674B3924D61FE74077C3DD9046D07A0" xlink:to="loc_us-gaap_MinimumMember_429FDD031DAAAC9537253DD9046DC764" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_1D7EFFCD18B84A4D102F3DD9046D27C3" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_E674B3924D61FE74077C3DD9046D07A0" xlink:to="loc_us-gaap_MaximumMember_1D7EFFCD18B84A4D102F3DD9046D27C3" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ExtendedProductWarrantyPeriod" xlink:label="loc_nstg_ExtendedProductWarrantyPeriod_7FAD72FAAB6351C8803B3DD9046DBF2D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_nstg_SignificantAccountingPoliciesLineItems_CD2700922D73505698A93DD9046DCB6E" xlink:to="loc_nstg_ExtendedProductWarrantyPeriod_7FAD72FAAB6351C8803B3DD9046DBF2D" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_StandardProductWarrantyPeriod" xlink:label="loc_nstg_StandardProductWarrantyPeriod_C8982B9B2B5E979E08CC3DD9046DD139" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_nstg_SignificantAccountingPoliciesLineItems_CD2700922D73505698A93DD9046DCB6E" xlink:to="loc_nstg_StandardProductWarrantyPeriod_C8982B9B2B5E979E08CC3DD9046DD139" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesPolicies" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/CollaborationAgreements" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/CollaborationAgreementsAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:label="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable" xlink:label="loc_us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_72AB28D4FF52B05C7A36F1EF49591F7D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_72AB28D4FF52B05C7A36F1EF49591F7D" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="loc_us-gaap_TypeOfArrangementAxis_017C46D9AB9590EEC36AF1EF49598426" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_72AB28D4FF52B05C7A36F1EF49591F7D" xlink:to="loc_us-gaap_TypeOfArrangementAxis_017C46D9AB9590EEC36AF1EF49598426" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_5866A0489528B3039CA8F1EF495A7BC6_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TypeOfArrangementAxis_017C46D9AB9590EEC36AF1EF49598426" xlink:to="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_5866A0489528B3039CA8F1EF495A7BC6_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_5866A0489528B3039CA8F1EF495A7BC6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TypeOfArrangementAxis_017C46D9AB9590EEC36AF1EF49598426" xlink:to="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_5866A0489528B3039CA8F1EF495A7BC6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CollaborativeArrangementMember" xlink:label="loc_us-gaap_CollaborativeArrangementMember_731967AFA04C6F0C08B6F1EF495A45FD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_5866A0489528B3039CA8F1EF495A7BC6" xlink:to="loc_us-gaap_CollaborativeArrangementMember_731967AFA04C6F0C08B6F1EF495A45FD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CounterpartyNameAxis" xlink:label="loc_us-gaap_CounterpartyNameAxis_394E75FD71207A13076AF1EF495A4E24" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_72AB28D4FF52B05C7A36F1EF49591F7D" xlink:to="loc_us-gaap_CounterpartyNameAxis_394E75FD71207A13076AF1EF495A4E24" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_20FBBAD9DC0C440788E1F1EF495B7CDC_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CounterpartyNameAxis_394E75FD71207A13076AF1EF495A4E24" xlink:to="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_20FBBAD9DC0C440788E1F1EF495B7CDC_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_20FBBAD9DC0C440788E1F1EF495B7CDC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CounterpartyNameAxis_394E75FD71207A13076AF1EF495A4E24" xlink:to="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_20FBBAD9DC0C440788E1F1EF495B7CDC" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_CelgeneCorporationMember" xlink:label="loc_nstg_CelgeneCorporationMember_E6DC813C5850533550FCF1EF495B2531" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_20FBBAD9DC0C440788E1F1EF495B7CDC" xlink:to="loc_nstg_CelgeneCorporationMember_E6DC813C5850533550FCF1EF495B2531" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_MerckSharpAndDohmeCorporationMember" xlink:label="loc_nstg_MerckSharpAndDohmeCorporationMember_4B1C11031D3D951F8FD6F1EF495BA158" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_20FBBAD9DC0C440788E1F1EF495B7CDC" xlink:to="loc_nstg_MerckSharpAndDohmeCorporationMember_4B1C11031D3D951F8FD6F1EF495BA158" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_LamResearchCorporationMember" xlink:label="loc_nstg_LamResearchCorporationMember_AB97F5216092BB736B11F1EF495C5F88" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_20FBBAD9DC0C440788E1F1EF495B7CDC" xlink:to="loc_nstg_LamResearchCorporationMember_AB97F5216092BB736B11F1EF495C5F88" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueArrangementTypeAxis" xlink:label="loc_us-gaap_DeferredRevenueArrangementTypeAxis_E1DFFFB4352AA23BABF4F1EF495CF490" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_72AB28D4FF52B05C7A36F1EF49591F7D" xlink:to="loc_us-gaap_DeferredRevenueArrangementTypeAxis_E1DFFFB4352AA23BABF4F1EF495CF490" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueArrangementTypeDomain" xlink:label="loc_us-gaap_DeferredRevenueArrangementTypeDomain_907D8231681462F360D8F1EF495C0373_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DeferredRevenueArrangementTypeAxis_E1DFFFB4352AA23BABF4F1EF495CF490" xlink:to="loc_us-gaap_DeferredRevenueArrangementTypeDomain_907D8231681462F360D8F1EF495C0373_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueArrangementTypeDomain" xlink:label="loc_us-gaap_DeferredRevenueArrangementTypeDomain_907D8231681462F360D8F1EF495C0373" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DeferredRevenueArrangementTypeAxis_E1DFFFB4352AA23BABF4F1EF495CF490" xlink:to="loc_us-gaap_DeferredRevenueArrangementTypeDomain_907D8231681462F360D8F1EF495C0373" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UpFrontPaymentArrangementMember" xlink:label="loc_us-gaap_UpFrontPaymentArrangementMember_7000C0342709DAEFC6E5F1EF495DE593" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DeferredRevenueArrangementTypeDomain_907D8231681462F360D8F1EF495C0373" xlink:to="loc_us-gaap_UpFrontPaymentArrangementMember_7000C0342709DAEFC6E5F1EF495DE593" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_AFBA3C16D68D144AC997F1EF495D90CD" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_72AB28D4FF52B05C7A36F1EF49591F7D" xlink:to="loc_us-gaap_RangeAxis_AFBA3C16D68D144AC997F1EF495D90CD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_3BA656E56E17A5A0F805F1EF495DE834_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_AFBA3C16D68D144AC997F1EF495D90CD" xlink:to="loc_us-gaap_RangeMember_3BA656E56E17A5A0F805F1EF495DE834_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_3BA656E56E17A5A0F805F1EF495DE834" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_AFBA3C16D68D144AC997F1EF495D90CD" xlink:to="loc_us-gaap_RangeMember_3BA656E56E17A5A0F805F1EF495DE834" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_9AA4B6269550198266D5F1EF4963736B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_3BA656E56E17A5A0F805F1EF495DE834" xlink:to="loc_us-gaap_MaximumMember_9AA4B6269550198266D5F1EF4963736B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LicenseAndServicesRevenue" xlink:label="loc_us-gaap_LicenseAndServicesRevenue_5C4DD949D4ADCA939C52F1EF4964377E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_us-gaap_LicenseAndServicesRevenue_5C4DD949D4ADCA939C52F1EF4964377E" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_MaximumAmountOfRoyaltiesPayableRatioToLicenseAndServiceRevenue" xlink:label="loc_nstg_MaximumAmountOfRoyaltiesPayableRatioToLicenseAndServiceRevenue_D94272944FF83B3EC2EEF1EF4964C435" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_nstg_MaximumAmountOfRoyaltiesPayableRatioToLicenseAndServiceRevenue_D94272944FF83B3EC2EEF1EF4964C435" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ReimbursementOfCounterpartyCostsMaximumNumberOfEmployees" xlink:label="loc_nstg_ReimbursementOfCounterpartyCostsMaximumNumberOfEmployees_7D99BCB93397A21EF649F1EF496421A7" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_nstg_ReimbursementOfCounterpartyCostsMaximumNumberOfEmployees_7D99BCB93397A21EF649F1EF496421A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ClassOfWarrantOrRightOutstanding" xlink:label="loc_us-gaap_ClassOfWarrantOrRightOutstanding_1A414E8CE944A0EE1607F1EF4964A092" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_us-gaap_ClassOfWarrantOrRightOutstanding_1A414E8CE944A0EE1607F1EF4964A092" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ExercisePriceOfCommonStockWarrants" xlink:label="loc_nstg_ExercisePriceOfCommonStockWarrants_EDBC2C713221BD2215EBF1EF49640D17" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_nstg_ExercisePriceOfCommonStockWarrants_EDBC2C713221BD2215EBF1EF49640D17" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockAndWarrantsIssuedDuringPeriodValuePreferredStockAndWarrants" xlink:label="loc_us-gaap_StockAndWarrantsIssuedDuringPeriodValuePreferredStockAndWarrants_6611835E91BF916C966AF1EF496509EC" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_us-gaap_StockAndWarrantsIssuedDuringPeriodValuePreferredStockAndWarrants_6611835E91BF916C966AF1EF496509EC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromCollaborators" xlink:label="loc_us-gaap_ProceedsFromCollaborators_6C617E06FD9E5F287197F1EF496510CC" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_us-gaap_ProceedsFromCollaborators_6C617E06FD9E5F287197F1EF496510CC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenue" xlink:label="loc_us-gaap_DeferredRevenue_B58217046F5115F4B412F1EF4965E419" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_us-gaap_DeferredRevenue_B58217046F5115F4B412F1EF4965E419" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="loc_us-gaap_DeferredRevenueCurrent_5CEE0D08419228A5E981F1EF49658B50" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_us-gaap_DeferredRevenueCurrent_5CEE0D08419228A5E981F1EF49658B50" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_CollaborativeAgreementPeriodOfContract" xlink:label="loc_nstg_CollaborativeAgreementPeriodOfContract_7B884E430F584E0807CFF1EF49656CC4" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_nstg_CollaborativeAgreementPeriodOfContract_7B884E430F584E0807CFF1EF49656CC4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherLiabilitiesCurrent_AF3DFA946389EE5EDA80F1EF4966A256" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_us-gaap_OtherLiabilitiesCurrent_AF3DFA946389EE5EDA80F1EF4966A256" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_Nstg_ReimbursementOfCounterpartyCosts" xlink:label="loc_nstg_Nstg_ReimbursementOfCounterpartyCosts_6D3C7E076E2185990554F1EF4966DDAC" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_nstg_Nstg_ReimbursementOfCounterpartyCosts_6D3C7E076E2185990554F1EF4966DDAC" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_CollaborativeAgreementAccruedCost" xlink:label="loc_nstg_CollaborativeAgreementAccruedCost_A72B7C08465F15438721F1EF496605EE" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_nstg_CollaborativeAgreementAccruedCost_A72B7C08465F15438721F1EF496605EE" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_PaymentsForCollaborativeAgreement" xlink:label="loc_nstg_PaymentsForCollaborativeAgreement_54506B4172BCCA9FDC73F1EF4966F2AF" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_nstg_PaymentsForCollaborativeAgreement_54506B4172BCCA9FDC73F1EF4966F2AF" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ClassOfWarrantOrRightNumberOfWarrantsOrRightsExercised" xlink:label="loc_nstg_ClassOfWarrantOrRightNumberOfWarrantsOrRightsExercised_8E21DE0B66205C99F430F1EF4966C82B" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_nstg_ClassOfWarrantOrRightNumberOfWarrantsOrRightsExercised_8E21DE0B66205C99F430F1EF4966C82B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized" xlink:label="loc_us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized_0F6E0C94125DCFFA5C52F1EF49667B0B" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized_0F6E0C94125DCFFA5C52F1EF49667B0B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueAdditions" xlink:label="loc_us-gaap_DeferredRevenueAdditions_0EF898FF52618699F703F1EF496CCD09" xlink:type="locator" />
    <link:definitionArc order="17" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_9C449B6071DE0524BDBAF1EF4963393B" xlink:to="loc_us-gaap_DeferredRevenueAdditions_0EF898FF52618699F703F1EF496CCD09" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/CommitmentsAndContingencies" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/ConcentrationOfRisks" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/ConcentrationOfRisksAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskLineItems" xlink:label="loc_us-gaap_ConcentrationRiskLineItems_4499D8BAF9061D7D50269DE97749B910" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskTable" xlink:label="loc_us-gaap_ConcentrationRiskTable_E23144E5870379E623399DE97746BB98" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_4499D8BAF9061D7D50269DE97749B910" xlink:to="loc_us-gaap_ConcentrationRiskTable_E23144E5870379E623399DE97746BB98" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorCustomersAxis" xlink:label="loc_us-gaap_MajorCustomersAxis_2E0091B9D413D72FD0839DE977463C37" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_E23144E5870379E623399DE97746BB98" xlink:to="loc_us-gaap_MajorCustomersAxis_2E0091B9D413D72FD0839DE977463C37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NameOfMajorCustomerDomain" xlink:label="loc_us-gaap_NameOfMajorCustomerDomain_5615E4A18AF724D541049DE977460EF2_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorCustomersAxis_2E0091B9D413D72FD0839DE977463C37" xlink:to="loc_us-gaap_NameOfMajorCustomerDomain_5615E4A18AF724D541049DE977460EF2_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NameOfMajorCustomerDomain" xlink:label="loc_us-gaap_NameOfMajorCustomerDomain_5615E4A18AF724D541049DE977460EF2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorCustomersAxis_2E0091B9D413D72FD0839DE977463C37" xlink:to="loc_us-gaap_NameOfMajorCustomerDomain_5615E4A18AF724D541049DE977460EF2" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_LamResearchCorporationMember" xlink:label="loc_nstg_LamResearchCorporationMember_0DC7BC3936D349774DE29DE9774733CE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NameOfMajorCustomerDomain_5615E4A18AF724D541049DE977460EF2" xlink:to="loc_nstg_LamResearchCorporationMember_0DC7BC3936D349774DE29DE9774733CE" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_MedivationInc.andAstellasPharmaInc.Member" xlink:label="loc_nstg_MedivationInc.andAstellasPharmaInc.Member_6C6EAE55729E69FB0A709DE977478AAF" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NameOfMajorCustomerDomain_5615E4A18AF724D541049DE977460EF2" xlink:to="loc_nstg_MedivationInc.andAstellasPharmaInc.Member_6C6EAE55729E69FB0A709DE977478AAF" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_MerckSharpAndDohmeCorporationMember" xlink:label="loc_nstg_MerckSharpAndDohmeCorporationMember_0EBA6830BF6618FA76B69DE97747133F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NameOfMajorCustomerDomain_5615E4A18AF724D541049DE977460EF2" xlink:to="loc_nstg_MerckSharpAndDohmeCorporationMember_0EBA6830BF6618FA76B69DE97747133F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskByTypeAxis" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_65205B7120CF2FA823399DE97747E6A3" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_E23144E5870379E623399DE97746BB98" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_65205B7120CF2FA823399DE97747E6A3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_1B6EAEF95B631106162D9DE977476185_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_65205B7120CF2FA823399DE97747E6A3" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_1B6EAEF95B631106162D9DE977476185_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_1B6EAEF95B631106162D9DE977476185" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_65205B7120CF2FA823399DE97747E6A3" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_1B6EAEF95B631106162D9DE977476185" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CustomerConcentrationRiskMember" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember_B189AB2EC4C32D2552F29DE977482D34" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_1B6EAEF95B631106162D9DE977476185" xlink:to="loc_us-gaap_CustomerConcentrationRiskMember_B189AB2EC4C32D2552F29DE977482D34" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_68EF300C9B1BB1F32AB49DE977482957" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_E23144E5870379E623399DE97746BB98" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_68EF300C9B1BB1F32AB49DE977482957" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_FEC1F9B5A6DE806A4CE29DE97748B6C7_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_68EF300C9B1BB1F32AB49DE977482957" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_FEC1F9B5A6DE806A4CE29DE97748B6C7_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_FEC1F9B5A6DE806A4CE29DE97748B6C7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_68EF300C9B1BB1F32AB49DE977482957" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_FEC1F9B5A6DE806A4CE29DE97748B6C7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SalesRevenueNetMember" xlink:label="loc_us-gaap_SalesRevenueNetMember_33633765ECBCDC3D3EF29DE97749935D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_FEC1F9B5A6DE806A4CE29DE97748B6C7" xlink:to="loc_us-gaap_SalesRevenueNetMember_33633765ECBCDC3D3EF29DE97749935D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskPercentage1" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_557BE27566E0AF79131A9DE977491D4A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_4499D8BAF9061D7D50269DE97749B910" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_557BE27566E0AF79131A9DE977491D4A" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/CondensedConsolidatedBalanceSheets" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/CondensedConsolidatedStatementsOfCashFlows" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_5818305635AEEBC80C58EBDB7ACE7F6A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_B8058AFE541BEB296523EBDB7ACDB26E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_5818305635AEEBC80C58EBDB7ACE7F6A" xlink:to="loc_us-gaap_StatementTable_B8058AFE541BEB296523EBDB7ACDB26E" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_4E37D4FBE0421723ECAAEBDB7ACDC414" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_B8058AFE541BEB296523EBDB7ACDB26E" xlink:to="loc_us-gaap_StatementScenarioAxis_4E37D4FBE0421723ECAAEBDB7ACDC414" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_A56C69E3398A2245F417EBDB7ACD2ECE_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementScenarioAxis_4E37D4FBE0421723ECAAEBDB7ACDC414" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_A56C69E3398A2245F417EBDB7ACD2ECE_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_A56C69E3398A2245F417EBDB7ACD2ECE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementScenarioAxis_4E37D4FBE0421723ECAAEBDB7ACDC414" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_A56C69E3398A2245F417EBDB7ACD2ECE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_7784507F590FA0646917EBDB7ACE97EE" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_B8058AFE541BEB296523EBDB7ACDB26E" xlink:to="loc_us-gaap_StatementClassOfStockAxis_7784507F590FA0646917EBDB7ACE97EE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_0A14B31C69791767B53AEBDB7ACE9CB8_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_7784507F590FA0646917EBDB7ACE97EE" xlink:to="loc_us-gaap_ClassOfStockDomain_0A14B31C69791767B53AEBDB7ACE9CB8_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_0A14B31C69791767B53AEBDB7ACE9CB8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_7784507F590FA0646917EBDB7ACE97EE" xlink:to="loc_us-gaap_ClassOfStockDomain_0A14B31C69791767B53AEBDB7ACE9CB8" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/CondensedConsolidatedStatementsOfComprehensiveLoss" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/CondensedConsolidatedStatementsOfOperations" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/DescriptionOfBusiness" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/DescriptionOfBusinessAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsidiarySaleOfStockLineItems" xlink:label="loc_us-gaap_SubsidiarySaleOfStockLineItems_4287E897ACCBB52900FEEA1EADFC36CF" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable" xlink:label="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_13BE1F588B079D006502EA1EADFA9B08" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_4287E897ACCBB52900FEEA1EADFC36CF" xlink:to="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_13BE1F588B079D006502EA1EADFA9B08" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_AE48884F1525A51FBB2FEA1EADFBFDD1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_13BE1F588B079D006502EA1EADFA9B08" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_AE48884F1525A51FBB2FEA1EADFBFDD1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_DF1E8A7F11B35576F07AEA1EADFB5680_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_AE48884F1525A51FBB2FEA1EADFBFDD1" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_DF1E8A7F11B35576F07AEA1EADFB5680_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_DF1E8A7F11B35576F07AEA1EADFB5680" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_AE48884F1525A51FBB2FEA1EADFBFDD1" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_DF1E8A7F11B35576F07AEA1EADFB5680" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_AtTheMarketEquityOfferingMember" xlink:label="loc_nstg_AtTheMarketEquityOfferingMember_60E926FA89E183386E6FEA1EADFB50B9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_DF1E8A7F11B35576F07AEA1EADFB5680" xlink:to="loc_nstg_AtTheMarketEquityOfferingMember_60E926FA89E183386E6FEA1EADFB50B9" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_PublicStockOfferingMember" xlink:label="loc_nstg_PublicStockOfferingMember_824F9F131FF88989046CEA3317020F2A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_DF1E8A7F11B35576F07AEA1EADFB5680" xlink:to="loc_nstg_PublicStockOfferingMember_824F9F131FF88989046CEA3317020F2A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OverAllotmentOptionMember" xlink:label="loc_us-gaap_OverAllotmentOptionMember_F3B96BF48AEA26CE062AEA452A3CC68D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_DF1E8A7F11B35576F07AEA1EADFB5680" xlink:to="loc_us-gaap_OverAllotmentOptionMember_F3B96BF48AEA26CE062AEA452A3CC68D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_56DC6C21046DE23D146FEA1EADFC655E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_4287E897ACCBB52900FEEA1EADFC36CF" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_56DC6C21046DE23D146FEA1EADFC655E" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_CommissionExpensePercentage" xlink:label="loc_nstg_CommissionExpensePercentage_E4293FE7943DEEDCE9DDEA1EADFD0A8C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_4287E897ACCBB52900FEEA1EADFC36CF" xlink:to="loc_nstg_CommissionExpensePercentage_E4293FE7943DEEDCE9DDEA1EADFD0A8C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_4A18AB07B701A513805AEA31FFAEF67D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_4287E897ACCBB52900FEEA1EADFC36CF" xlink:to="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_4A18AB07B701A513805AEA31FFAEF67D" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_SaleOfStockGrossConsiderationReceivedOnTransaction" xlink:label="loc_nstg_SaleOfStockGrossConsiderationReceivedOnTransaction_4ECC3A4C851089612D19EA34DE8A15AA" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_4287E897ACCBB52900FEEA1EADFC36CF" xlink:to="loc_nstg_SaleOfStockGrossConsiderationReceivedOnTransaction_4ECC3A4C851089612D19EA34DE8A15AA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_69843C203BA8A7BC644EEA37ED0685D1" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_4287E897ACCBB52900FEEA1EADFC36CF" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_69843C203BA8A7BC644EEA37ED0685D1" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/DocumentAndEntityInformation" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/FairValueMeasurements" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/FairValueMeasurementsCompanysAvailableForSaleSecuritiesByLevelWithinFairValueHierarchyDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_B2BC8969D09C59ADFA8AF1A66CF5D40D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8F29AAAC8EC1B390BD1DF1A66CE58CB4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_B2BC8969D09C59ADFA8AF1A66CF5D40D" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8F29AAAC8EC1B390BD1DF1A66CE58CB4" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_DADFD7799F17ED5726E2F1A66CE58A94" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8F29AAAC8EC1B390BD1DF1A66CE58CB4" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_DADFD7799F17ED5726E2F1A66CE58A94" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1DFCBC29E51B2D1E7848F1A66CE58614_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_DADFD7799F17ED5726E2F1A66CE58A94" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1DFCBC29E51B2D1E7848F1A66CE58614_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1DFCBC29E51B2D1E7848F1A66CE58614" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_DADFD7799F17ED5726E2F1A66CE58A94" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1DFCBC29E51B2D1E7848F1A66CE58614" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_4086FB3BE7B7756F17DAF1A66CE54720" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1DFCBC29E51B2D1E7848F1A66CE58614" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_4086FB3BE7B7756F17DAF1A66CE54720" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_0DC0B55C1752140CCBE2F1A66CE5C9FD" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1DFCBC29E51B2D1E7848F1A66CE58614" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_0DC0B55C1752140CCBE2F1A66CE5C9FD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_CEEEA90A28B08B3BF44CF1A66CE50A3F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_1DFCBC29E51B2D1E7848F1A66CE58614" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_CEEEA90A28B08B3BF44CF1A66CE50A3F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsAxis" xlink:label="loc_us-gaap_CashAndCashEquivalentsAxis_E1CF2E74E4EE240DC2FBF1A66CE54ED0" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8F29AAAC8EC1B390BD1DF1A66CE58CB4" xlink:to="loc_us-gaap_CashAndCashEquivalentsAxis_E1CF2E74E4EE240DC2FBF1A66CE54ED0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_25D369588F7F6B4D63DAF1A66CE551F8_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_E1CF2E74E4EE240DC2FBF1A66CE54ED0" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_25D369588F7F6B4D63DAF1A66CE551F8_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_25D369588F7F6B4D63DAF1A66CE551F8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_E1CF2E74E4EE240DC2FBF1A66CE54ED0" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_25D369588F7F6B4D63DAF1A66CE551F8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MoneyMarketFundsMember" xlink:label="loc_us-gaap_MoneyMarketFundsMember_5E6B2FAC9FDAD7CFBB8DF1A66CE5448D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_25D369588F7F6B4D63DAF1A66CE551F8" xlink:to="loc_us-gaap_MoneyMarketFundsMember_5E6B2FAC9FDAD7CFBB8DF1A66CE5448D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_AD9218BC2A41AF5D3F34F1A66CE5910F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8F29AAAC8EC1B390BD1DF1A66CE58CB4" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_AD9218BC2A41AF5D3F34F1A66CE5910F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_6032218E2B553C4439E2F1A66CE51FDC_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_AD9218BC2A41AF5D3F34F1A66CE5910F" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_6032218E2B553C4439E2F1A66CE51FDC_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_6032218E2B553C4439E2F1A66CE51FDC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_AD9218BC2A41AF5D3F34F1A66CE5910F" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_6032218E2B553C4439E2F1A66CE51FDC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CorporateDebtSecuritiesMember" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_697C79FD243A29FDAE29F1A66CF53E2E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_6032218E2B553C4439E2F1A66CE51FDC" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_697C79FD243A29FDAE29F1A66CF53E2E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_3A93610D61013CB5D38AF1A66CF5F29C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_6032218E2B553C4439E2F1A66CE51FDC" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_3A93610D61013CB5D38AF1A66CF5F29C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_91641357B37ACE539ED1F1A6999A89AA" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_6032218E2B553C4439E2F1A66CE51FDC" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_91641357B37ACE539ED1F1A6999A89AA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_38F91F0A1B00DB1C036CF1A66CF57564" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_B2BC8969D09C59ADFA8AF1A66CF5D40D" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_38F91F0A1B00DB1C036CF1A66CF57564" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesCurrent" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesCurrent_594CC1736E02288A2E4DF1A66CF5A47D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_B2BC8969D09C59ADFA8AF1A66CF5D40D" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesCurrent_594CC1736E02288A2E4DF1A66CF5A47D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AssetsFairValueDisclosure" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_DA389E2E06EDE0BEC6A3F1A66CF542AD" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_B2BC8969D09C59ADFA8AF1A66CF5D40D" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_DA389E2E06EDE0BEC6A3F1A66CF542AD" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/FairValueMeasurementsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/InformationAboutGeographicAreas" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/InformationAboutGeographicAreasAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_81C455D408B5C223C57CB483BC92E1C9" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_A4431D58CB9768BFB1D5B483BC91C59D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_81C455D408B5C223C57CB483BC92E1C9" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_A4431D58CB9768BFB1D5B483BC91C59D" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementGeographicalAxis" xlink:label="loc_us-gaap_StatementGeographicalAxis_75CCCFA7C9F9DB9A6448B483BC910FA2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_A4431D58CB9768BFB1D5B483BC91C59D" xlink:to="loc_us-gaap_StatementGeographicalAxis_75CCCFA7C9F9DB9A6448B483BC910FA2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="loc_us-gaap_SegmentGeographicalDomain_1CA0F63FFB7391AAC354B483BC92D17D_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementGeographicalAxis_75CCCFA7C9F9DB9A6448B483BC910FA2" xlink:to="loc_us-gaap_SegmentGeographicalDomain_1CA0F63FFB7391AAC354B483BC92D17D_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="loc_us-gaap_SegmentGeographicalDomain_1CA0F63FFB7391AAC354B483BC92D17D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementGeographicalAxis_75CCCFA7C9F9DB9A6448B483BC910FA2" xlink:to="loc_us-gaap_SegmentGeographicalDomain_1CA0F63FFB7391AAC354B483BC92D17D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_US" xlink:label="loc_country_US_4CEF829C939B589FCB74B483BC927FE9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentGeographicalDomain_1CA0F63FFB7391AAC354B483BC92D17D" xlink:to="loc_country_US_4CEF829C939B589FCB74B483BC927FE9" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_NumberOfSalesForces" xlink:label="loc_nstg_NumberOfSalesForces_66B64AF6C0E80B16133BB483BC93E9E2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_81C455D408B5C223C57CB483BC92E1C9" xlink:to="loc_nstg_NumberOfSalesForces_66B64AF6C0E80B16133BB483BC93E9E2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NumberOfReportableSegments" xlink:label="loc_us-gaap_NumberOfReportableSegments_3BB458655A4B9265FBA3B483BC93A1C5" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_81C455D408B5C223C57CB483BC92E1C9" xlink:to="loc_us-gaap_NumberOfReportableSegments_3BB458655A4B9265FBA3B483BC93A1C5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_50429D64985C23DA4262B483BC93705C" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_81C455D408B5C223C57CB483BC92E1C9" xlink:to="loc_us-gaap_Revenues_50429D64985C23DA4262B483BC93705C" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/InformationAboutGeographicAreasClassificationOfRevenueByGeographyDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_F9383B6D1F5290139327F32C6BFE0A0E" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_396E4FBD6D3DE7E04609F32C6BFEA4CA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_F9383B6D1F5290139327F32C6BFE0A0E" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_396E4FBD6D3DE7E04609F32C6BFEA4CA" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementGeographicalAxis" xlink:label="loc_us-gaap_StatementGeographicalAxis_DB9999E4571F6DAD9459F32C6BFEA045" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_396E4FBD6D3DE7E04609F32C6BFEA4CA" xlink:to="loc_us-gaap_StatementGeographicalAxis_DB9999E4571F6DAD9459F32C6BFEA045" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="loc_us-gaap_SegmentGeographicalDomain_7899F9B3E65ED0BC741BF32C6BFE034B_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementGeographicalAxis_DB9999E4571F6DAD9459F32C6BFEA045" xlink:to="loc_us-gaap_SegmentGeographicalDomain_7899F9B3E65ED0BC741BF32C6BFE034B_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="loc_us-gaap_SegmentGeographicalDomain_7899F9B3E65ED0BC741BF32C6BFE034B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementGeographicalAxis_DB9999E4571F6DAD9459F32C6BFEA045" xlink:to="loc_us-gaap_SegmentGeographicalDomain_7899F9B3E65ED0BC741BF32C6BFE034B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AmericasMember" xlink:label="loc_us-gaap_AmericasMember_CC0A6F1A94DAC853BFE3F32C6BFE3D1C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentGeographicalDomain_7899F9B3E65ED0BC741BF32C6BFE034B" xlink:to="loc_us-gaap_AmericasMember_CC0A6F1A94DAC853BFE3F32C6BFE3D1C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EMEAMember" xlink:label="loc_us-gaap_EMEAMember_6FB84A1168540D1C2B19F32C6BFE9B1F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentGeographicalDomain_7899F9B3E65ED0BC741BF32C6BFE034B" xlink:to="loc_us-gaap_EMEAMember_6FB84A1168540D1C2B19F32C6BFE9B1F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AsiaPacificMember" xlink:label="loc_us-gaap_AsiaPacificMember_302F1CCE8EB747D275AFF32C6BFEABC5" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentGeographicalDomain_7899F9B3E65ED0BC741BF32C6BFE034B" xlink:to="loc_us-gaap_AsiaPacificMember_302F1CCE8EB747D275AFF32C6BFEABC5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_B02D07AB299EFFC13691F32C6BFEDCF8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_F9383B6D1F5290139327F32C6BFE0A0E" xlink:to="loc_us-gaap_Revenues_B02D07AB299EFFC13691F32C6BFEDCF8" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/InformationAboutGeographicAreasTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/Inventory" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/InventoryScheduleOfInventoryDetail" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/InventoryTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/LongTermDebt" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/LongTermDebtAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityLineItems" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityTable" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_AAE0AF036D5408BAC5B1400F2B73772C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_us-gaap_LineOfCreditFacilityTable_AAE0AF036D5408BAC5B1400F2B73772C" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateAxis" xlink:label="loc_us-gaap_VariableRateAxis_76771D341E8D45B7B1D3400F2B73E636" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_AAE0AF036D5408BAC5B1400F2B73772C" xlink:to="loc_us-gaap_VariableRateAxis_76771D341E8D45B7B1D3400F2B73E636" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_078168B0FCABFC985D3E400F2B731183_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_76771D341E8D45B7B1D3400F2B73E636" xlink:to="loc_us-gaap_VariableRateDomain_078168B0FCABFC985D3E400F2B731183_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_078168B0FCABFC985D3E400F2B731183" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_76771D341E8D45B7B1D3400F2B73E636" xlink:to="loc_us-gaap_VariableRateDomain_078168B0FCABFC985D3E400F2B731183" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PrimeRateMember" xlink:label="loc_us-gaap_PrimeRateMember_D95322E5EAE09AFC7321400F2B7342C8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_078168B0FCABFC985D3E400F2B731183" xlink:to="loc_us-gaap_PrimeRateMember_D95322E5EAE09AFC7321400F2B7342C8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_6F6AF3FE352412AB341C400F2B73091E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_AAE0AF036D5408BAC5B1400F2B73772C" xlink:to="loc_us-gaap_CreditFacilityAxis_6F6AF3FE352412AB341C400F2B73091E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_A9E7F564AD1BA257C554400F2B73724F_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_6F6AF3FE352412AB341C400F2B73091E" xlink:to="loc_us-gaap_CreditFacilityDomain_A9E7F564AD1BA257C554400F2B73724F_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_A9E7F564AD1BA257C554400F2B73724F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_6F6AF3FE352412AB341C400F2B73091E" xlink:to="loc_us-gaap_CreditFacilityDomain_A9E7F564AD1BA257C554400F2B73724F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_7C4E60CB16735AE20E9F400F2B737B2C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_A9E7F564AD1BA257C554400F2B73724F" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_7C4E60CB16735AE20E9F400F2B737B2C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_73259A71CA97A5901BA3400F2B73D5B8" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_AAE0AF036D5408BAC5B1400F2B73772C" xlink:to="loc_us-gaap_DebtInstrumentAxis_73259A71CA97A5901BA3400F2B73D5B8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_F6DCF7D61F42123C1622400F2B73B490_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_73259A71CA97A5901BA3400F2B73D5B8" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_F6DCF7D61F42123C1622400F2B73B490_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_F6DCF7D61F42123C1622400F2B73B490" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_73259A71CA97A5901BA3400F2B73D5B8" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_F6DCF7D61F42123C1622400F2B73B490" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_TermLoanAgreementMember" xlink:label="loc_nstg_TermLoanAgreementMember_643B3FEB20A116763270400F2B739519" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_F6DCF7D61F42123C1622400F2B73B490" xlink:to="loc_nstg_TermLoanAgreementMember_643B3FEB20A116763270400F2B739519" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_SecuredRevolvingLoanFacilityMember" xlink:label="loc_nstg_SecuredRevolvingLoanFacilityMember_B86BBDB6C7BD7CD715AC400F2B73E2CE" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_F6DCF7D61F42123C1622400F2B73B490" xlink:to="loc_nstg_SecuredRevolvingLoanFacilityMember_B86BBDB6C7BD7CD715AC400F2B73E2CE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_9BA52F85F8460948B8DE400F2B739435" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_AAE0AF036D5408BAC5B1400F2B73772C" xlink:to="loc_us-gaap_RangeAxis_9BA52F85F8460948B8DE400F2B739435" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_C7B94F6DF3ADD51E3CB1400F2B735C2B_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_9BA52F85F8460948B8DE400F2B739435" xlink:to="loc_us-gaap_RangeMember_C7B94F6DF3ADD51E3CB1400F2B735C2B_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_C7B94F6DF3ADD51E3CB1400F2B735C2B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_9BA52F85F8460948B8DE400F2B739435" xlink:to="loc_us-gaap_RangeMember_C7B94F6DF3ADD51E3CB1400F2B735C2B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_AC0F96CF37B73DF1188D400F2B73FD97" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_C7B94F6DF3ADD51E3CB1400F2B735C2B" xlink:to="loc_us-gaap_MaximumMember_AC0F96CF37B73DF1188D400F2B73FD97" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_63EEDF9E5C084E87A99A400F2B741E21" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_AAE0AF036D5408BAC5B1400F2B73772C" xlink:to="loc_us-gaap_StatementScenarioAxis_63EEDF9E5C084E87A99A400F2B741E21" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_688172F36452EA2E8472400F2B740CC9_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementScenarioAxis_63EEDF9E5C084E87A99A400F2B741E21" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_688172F36452EA2E8472400F2B740CC9_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_688172F36452EA2E8472400F2B740CC9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementScenarioAxis_63EEDF9E5C084E87A99A400F2B741E21" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_688172F36452EA2E8472400F2B740CC9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_D653EDE17ABFE112E1F6400F2B7474C0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_D653EDE17ABFE112E1F6400F2B7474C0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_0719584D2E1B59EC9393400F2B74C265" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_0719584D2E1B59EC9393400F2B74C265" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_LineCreditFacilityAdditionalBorrowingCapacity" xlink:label="loc_nstg_LineCreditFacilityAdditionalBorrowingCapacity_5562100209F5B330A183400F2B744449" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_nstg_LineCreditFacilityAdditionalBorrowingCapacity_5562100209F5B330A183400F2B744449" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount" xlink:label="loc_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount_7C4BF858D3742A87D49D400F2B743607" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount_7C4BF858D3742A87D49D400F2B743607" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtPercentageBearingFixedInterestRate" xlink:label="loc_us-gaap_LongTermDebtPercentageBearingFixedInterestRate_F614DE5A4DCF20E89F3C400F2B74B1D6" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_us-gaap_LongTermDebtPercentageBearingFixedInterestRate_F614DE5A4DCF20E89F3C400F2B74B1D6" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_DeferredPaymentObligationAccruedInterestRate" xlink:label="loc_nstg_DeferredPaymentObligationAccruedInterestRate_EAE933C37BE717B4AEB3400F2B7433C2" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_nstg_DeferredPaymentObligationAccruedInterestRate_EAE933C37BE717B4AEB3400F2B7433C2" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_DebtInstrumentInterestDeferralPeriod" xlink:label="loc_nstg_DebtInstrumentInterestDeferralPeriod_7D5AE8859257CA110006400F2B749FCD" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_nstg_DebtInstrumentInterestDeferralPeriod_7D5AE8859257CA110006400F2B749FCD" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_DebtDeferredInterestPayment" xlink:label="loc_nstg_DebtDeferredInterestPayment_D7D8255CDDB01BFD15FA400F2B742BF3" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_nstg_DebtDeferredInterestPayment_D7D8255CDDB01BFD15FA400F2B742BF3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LoansPayable" xlink:label="loc_us-gaap_LoansPayable_7BE4C7FCA28748D14CD8400F2B74CB73" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_us-gaap_LoansPayable_7BE4C7FCA28748D14CD8400F2B74CB73" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_DebtInstrumentInterestPaymentPeriod" xlink:label="loc_nstg_DebtInstrumentInterestPaymentPeriod_F4E96B74D7ABFF39A350400F2B74B424" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_nstg_DebtInstrumentInterestPaymentPeriod_F4E96B74D7ABFF39A350400F2B74B424" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_DebtInstrumentNumberOfInstallmentsDuringEighthYearOfTerm" xlink:label="loc_nstg_DebtInstrumentNumberOfInstallmentsDuringEighthYearOfTerm_A05A7038E4952762397C400F2B74E4F4" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_nstg_DebtInstrumentNumberOfInstallmentsDuringEighthYearOfTerm_A05A7038E4952762397C400F2B74E4F4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityCommitmentFeePercentage" xlink:label="loc_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_658C4C1B108D277530EC400F2B74BE89" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_658C4C1B108D277530EC400F2B74BE89" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermLineOfCredit" xlink:label="loc_us-gaap_LongTermLineOfCredit_DA46E38F28FD1B72EFC0400F2B74B1BE" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_us-gaap_LongTermLineOfCredit_DA46E38F28FD1B72EFC0400F2B74B1BE" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_MinimumLiquidityCovenantAmount" xlink:label="loc_nstg_MinimumLiquidityCovenantAmount_313FE18931023EF42523400F2B7450F7" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_nstg_MinimumLiquidityCovenantAmount_313FE18931023EF42523400F2B7450F7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized" xlink:label="loc_us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized_CC186EF6E83596CC2837400F2B747527" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized_CC186EF6E83596CC2837400F2B747527" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_IncreasedAnnualRevenues" xlink:label="loc_nstg_IncreasedAnnualRevenues_683B0B30FA7FAD2B0606400F2B748C0E" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_nstg_IncreasedAnnualRevenues_683B0B30FA7FAD2B0606400F2B748C0E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaap_LineOfCredit_C0E3C307975A44887D7C400F2B745D4A" xlink:type="locator" />
    <link:definitionArc order="17" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_45B6EBB14E0E340921FB400F2B74FF6D" xlink:to="loc_us-gaap_LineOfCredit_C0E3C307975A44887D7C400F2B745D4A" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/LongTermDebtComponentsOfBorrowingsIncludingCurrentPortionDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_87DB6C07271CF0CF5A8C400F2B6DF1B0" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_3986312E25BFBE95662C400F2B6C8325" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_87DB6C07271CF0CF5A8C400F2B6DF1B0" xlink:to="loc_us-gaap_DebtInstrumentTable_3986312E25BFBE95662C400F2B6C8325" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_886DEE9704190480333C400F2B6CAD06" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_3986312E25BFBE95662C400F2B6C8325" xlink:to="loc_us-gaap_DebtInstrumentAxis_886DEE9704190480333C400F2B6CAD06" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_AB892C4C7B6CEEC7227A400F2B6CDAF7_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_886DEE9704190480333C400F2B6CAD06" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_AB892C4C7B6CEEC7227A400F2B6CDAF7_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_AB892C4C7B6CEEC7227A400F2B6CDAF7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_886DEE9704190480333C400F2B6CAD06" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_AB892C4C7B6CEEC7227A400F2B6CDAF7" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_TermLoanAgreementMember" xlink:label="loc_nstg_TermLoanAgreementMember_48D5F568FA2358420636400F2B6D1D97" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_AB892C4C7B6CEEC7227A400F2B6CDAF7" xlink:to="loc_nstg_TermLoanAgreementMember_48D5F568FA2358420636400F2B6D1D97" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LoansPayable" xlink:label="loc_us-gaap_LoansPayable_5B9ADDFF57771B7B9F18400F2B6D4291" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_87DB6C07271CF0CF5A8C400F2B6DF1B0" xlink:to="loc_us-gaap_LoansPayable_5B9ADDFF57771B7B9F18400F2B6D4291" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnamortizedDebtIssuanceExpense" xlink:label="loc_us-gaap_UnamortizedDebtIssuanceExpense_CB10277F36EE10D29213400F2B6D21DB" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_87DB6C07271CF0CF5A8C400F2B6DF1B0" xlink:to="loc_us-gaap_UnamortizedDebtIssuanceExpense_CB10277F36EE10D29213400F2B6D21DB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligations" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_9E4DA6CDCB65BEC14F3E400F2B6DFCE2" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_87DB6C07271CF0CF5A8C400F2B6DF1B0" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_9E4DA6CDCB65BEC14F3E400F2B6DFCE2" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/LongTermDebtScheduledFuturePrincipalPaymentsUnderOutstandingDebtObligationsDetail" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/LongTermDebtTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/NetLossPerShare" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/NetLossPerShareSummaryOfSharesUnderlyingOutstandingOptionsAndWarrantsWereExcludedFromComputationOfBasicAndDilutedNetLossPerShareDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_5CDDA8AD5DC6772315ACF32C6BC0B672" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_D4AD44CC2F2F29C7498DF32C6BC0F48E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_5CDDA8AD5DC6772315ACF32C6BC0B672" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_D4AD44CC2F2F29C7498DF32C6BC0F48E" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5D1902E37DFBF6F0D447F32C6BC08AAE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_D4AD44CC2F2F29C7498DF32C6BC0F48E" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5D1902E37DFBF6F0D447F32C6BC08AAE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_94766C3CF61691636D9AF32C6BC0D759_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5D1902E37DFBF6F0D447F32C6BC08AAE" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_94766C3CF61691636D9AF32C6BC0D759_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_94766C3CF61691636D9AF32C6BC0D759" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5D1902E37DFBF6F0D447F32C6BC08AAE" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_94766C3CF61691636D9AF32C6BC0D759" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="loc_us-gaap_EmployeeStockOptionMember_4072D7191485F43CF62FF32C6BC0CB3D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_94766C3CF61691636D9AF32C6BC0D759" xlink:to="loc_us-gaap_EmployeeStockOptionMember_4072D7191485F43CF62FF32C6BC0CB3D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_BF249FC1F4B47D61FB11F32C6BC05CDF" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_94766C3CF61691636D9AF32C6BC0D759" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_BF249FC1F4B47D61FB11F32C6BC05CDF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WarrantMember" xlink:label="loc_us-gaap_WarrantMember_8AC8F6D86727C3327C04F32C6BC0C87B" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_94766C3CF61691636D9AF32C6BC0D759" xlink:to="loc_us-gaap_WarrantMember_8AC8F6D86727C3327C04F32C6BC0C87B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_3E94939CB59169D46428F32C6BC02934" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_D4AD44CC2F2F29C7498DF32C6BC0F48E" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_3E94939CB59169D46428F32C6BC02934" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_063A2BA4FB209FA760DEF32C6BC0669F_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_3E94939CB59169D46428F32C6BC02934" xlink:to="loc_us-gaap_EquityComponentDomain_063A2BA4FB209FA760DEF32C6BC0669F_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_063A2BA4FB209FA760DEF32C6BC0669F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_3E94939CB59169D46428F32C6BC02934" xlink:to="loc_us-gaap_EquityComponentDomain_063A2BA4FB209FA760DEF32C6BC0669F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_24525518508184A1F518F32C6BC019B7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_063A2BA4FB209FA760DEF32C6BC0669F" xlink:to="loc_us-gaap_CommonStockMember_24525518508184A1F518F32C6BC019B7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_9C517BA2C7EAF2E000BBF32C6BC04CE3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_5CDDA8AD5DC6772315ACF32C6BC0B672" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_9C517BA2C7EAF2E000BBF32C6BC04CE3" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/NetLossPerShareTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/RevenueFromContractsWithCustomersNarrativeDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems" xlink:label="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_0CD60D02C4B52C8E5C79EC20D9FBE492" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable" xlink:label="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_77CAAEACB3F59D89DE29EC20D9F85091" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_0CD60D02C4B52C8E5C79EC20D9FBE492" xlink:to="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_77CAAEACB3F59D89DE29EC20D9F85091" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_5B420EF7463474BBAC37EC20D9F83CB8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_77CAAEACB3F59D89DE29EC20D9F85091" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_5B420EF7463474BBAC37EC20D9F83CB8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_44AC0F9054E2985C7675EC20D9F94457_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_5B420EF7463474BBAC37EC20D9F83CB8" xlink:to="loc_us-gaap_EquityComponentDomain_44AC0F9054E2985C7675EC20D9F94457_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_44AC0F9054E2985C7675EC20D9F94457" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_5B420EF7463474BBAC37EC20D9F83CB8" xlink:to="loc_us-gaap_EquityComponentDomain_44AC0F9054E2985C7675EC20D9F94457" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_B485028F58A09D01D61FEC20D9F9A494" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_44AC0F9054E2985C7675EC20D9F94457" xlink:to="loc_us-gaap_RetainedEarningsMember_B485028F58A09D01D61FEC20D9F9A494" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_D6DB7DF6E3F78D010EF1EC20D9FA9353" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_77CAAEACB3F59D89DE29EC20D9F85091" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_D6DB7DF6E3F78D010EF1EC20D9FA9353" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_D1415660C03DDF014AE8EC20D9FAB78F_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_D6DB7DF6E3F78D010EF1EC20D9FA9353" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_D1415660C03DDF014AE8EC20D9FAB78F_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_D1415660C03DDF014AE8EC20D9FAB78F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_D6DB7DF6E3F78D010EF1EC20D9FA9353" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_D1415660C03DDF014AE8EC20D9FAB78F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member" xlink:label="loc_us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member_A6B66BF80B06286CED7BEC20D9FAD79D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_D1415660C03DDF014AE8EC20D9FAB78F" xlink:to="loc_us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member_A6B66BF80B06286CED7BEC20D9FAD79D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member" xlink:label="loc_us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member_12F717299DD908BB6240EC20D9FA0E52" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_D1415660C03DDF014AE8EC20D9FAB78F" xlink:to="loc_us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member_12F717299DD908BB6240EC20D9FA0E52" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_95F97A565736133DF82BEC20D9FB3097" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_77CAAEACB3F59D89DE29EC20D9F85091" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_95F97A565736133DF82BEC20D9FB3097" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_2A2145432DB4DAC78069EC20D9FBD9F3_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_95F97A565736133DF82BEC20D9FB3097" xlink:to="loc_us-gaap_TypeOfAdoptionMember_2A2145432DB4DAC78069EC20D9FBD9F3_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_2A2145432DB4DAC78069EC20D9FBD9F3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_95F97A565736133DF82BEC20D9FB3097" xlink:to="loc_us-gaap_TypeOfAdoptionMember_2A2145432DB4DAC78069EC20D9FBD9F3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingStandardsUpdate201409Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201409Member_63DA1346193D876C7E1CEC20D9FB6817" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_2A2145432DB4DAC78069EC20D9FBD9F3" xlink:to="loc_us-gaap_AccountingStandardsUpdate201409Member_63DA1346193D876C7E1CEC20D9FB6817" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption" xlink:label="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_5AF7B9A3B20476BE3E95EC20D9FC89FF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_0CD60D02C4B52C8E5C79EC20D9FBE492" xlink:to="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_5AF7B9A3B20476BE3E95EC20D9FC89FF" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoptionRevenueRecognized" xlink:label="loc_nstg_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoptionRevenueRecognized_E6C5520CCD0DFEE521CAEC20D9FCEA5C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_0CD60D02C4B52C8E5C79EC20D9FBE492" xlink:to="loc_nstg_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoptionRevenueRecognized_E6C5520CCD0DFEE521CAEC20D9FCEA5C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CustomerDepositsCurrent" xlink:label="loc_us-gaap_CustomerDepositsCurrent_3D4174BE508670F509E0EC20D9FC212F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_0CD60D02C4B52C8E5C79EC20D9FBE492" xlink:to="loc_us-gaap_CustomerDepositsCurrent_3D4174BE508670F509E0EC20D9FC212F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerLiability" xlink:label="loc_us-gaap_ContractWithCustomerLiability_562580C50448BB60D131EC20D9FCEF49" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_0CD60D02C4B52C8E5C79EC20D9FBE492" xlink:to="loc_us-gaap_ContractWithCustomerLiability_562580C50448BB60D131EC20D9FCEF49" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod" xlink:label="loc_us-gaap_ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod_D003B87284E166961000EC20D9FD5FAA" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_0CD60D02C4B52C8E5C79EC20D9FBE492" xlink:to="loc_us-gaap_ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod_D003B87284E166961000EC20D9FD5FAA" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ContractWithCustomerLiabilityIncreaseFromCashReceipts" xlink:label="loc_nstg_ContractWithCustomerLiabilityIncreaseFromCashReceipts_76A85C22197465A4E059EC20D9FDB8B6" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_0CD60D02C4B52C8E5C79EC20D9FBE492" xlink:to="loc_nstg_ContractWithCustomerLiabilityIncreaseFromCashReceipts_76A85C22197465A4E059EC20D9FDB8B6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerAssetNet" xlink:label="loc_us-gaap_ContractWithCustomerAssetNet_E2771A979C309A3FF8AFEC20D9FDD274" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_0CD60D02C4B52C8E5C79EC20D9FBE492" xlink:to="loc_us-gaap_ContractWithCustomerAssetNet_E2771A979C309A3FF8AFEC20D9FDD274" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligation" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation_39029867E23645C7B9B4EC20D9FD947D" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_0CD60D02C4B52C8E5C79EC20D9FBE492" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligation_39029867E23645C7B9B4EC20D9FD947D" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/RevenueFromContractsWithCustomersNotes" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/RevenueFromContractsWithCustomersPerformanceObligationsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_398E0749A514CF0E216141775D6ADC24" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_944DE61296854B0D340141775D68983C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_398E0749A514CF0E216141775D6ADC24" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_944DE61296854B0D340141775D68983C" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductOrServiceAxis" xlink:label="loc_us-gaap_ProductOrServiceAxis_C40DF87C7A8F7BDC30FF417EC7E56976" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_944DE61296854B0D340141775D68983C" xlink:to="loc_us-gaap_ProductOrServiceAxis_C40DF87C7A8F7BDC30FF417EC7E56976" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="loc_us-gaap_ProductsAndServicesDomain_152C70B94DBECB12A43C417EC880F740_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ProductOrServiceAxis_C40DF87C7A8F7BDC30FF417EC7E56976" xlink:to="loc_us-gaap_ProductsAndServicesDomain_152C70B94DBECB12A43C417EC880F740_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="loc_us-gaap_ProductsAndServicesDomain_152C70B94DBECB12A43C417EC880F740" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ProductOrServiceAxis_C40DF87C7A8F7BDC30FF417EC7E56976" xlink:to="loc_us-gaap_ProductsAndServicesDomain_152C70B94DBECB12A43C417EC880F740" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_TotalProductsAndServicesMember" xlink:label="loc_nstg_TotalProductsAndServicesMember_C219EF559E3143FC6B7F417EC8431671" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_152C70B94DBECB12A43C417EC880F740" xlink:to="loc_nstg_TotalProductsAndServicesMember_C219EF559E3143FC6B7F417EC8431671" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_50FE2AC5C0B97A97F08F41775D6A3620" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_944DE61296854B0D340141775D68983C" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_50FE2AC5C0B97A97F08F41775D6A3620" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligation" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation_3C0A68C7BE174C07374241775D6A953C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_398E0749A514CF0E216141775D6ADC24" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligation_3C0A68C7BE174C07374241775D6A953C" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/RevenueFromContractsWithCustomersScheduleOfDisaggregatedRevenueDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems" xlink:label="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_9A4EBED548015C672F7DF8AB1AF1949C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable" xlink:label="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_1DDC4904711A7416F3B8F8AB1AED436F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_9A4EBED548015C672F7DF8AB1AF1949C" xlink:to="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_1DDC4904711A7416F3B8F8AB1AED436F" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementGeographicalAxis" xlink:label="loc_us-gaap_StatementGeographicalAxis_92B647532558C0D41918F8AB1AEE9917" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_1DDC4904711A7416F3B8F8AB1AED436F" xlink:to="loc_us-gaap_StatementGeographicalAxis_92B647532558C0D41918F8AB1AEE9917" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="loc_us-gaap_SegmentGeographicalDomain_0FC07FB91B4E910CA71EF8AB1AEEEFC6_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementGeographicalAxis_92B647532558C0D41918F8AB1AEE9917" xlink:to="loc_us-gaap_SegmentGeographicalDomain_0FC07FB91B4E910CA71EF8AB1AEEEFC6_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="loc_us-gaap_SegmentGeographicalDomain_0FC07FB91B4E910CA71EF8AB1AEEEFC6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementGeographicalAxis_92B647532558C0D41918F8AB1AEE9917" xlink:to="loc_us-gaap_SegmentGeographicalDomain_0FC07FB91B4E910CA71EF8AB1AEEEFC6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AmericasMember" xlink:label="loc_us-gaap_AmericasMember_E840553F042D39CDE5EBF8AB1AEE2233" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentGeographicalDomain_0FC07FB91B4E910CA71EF8AB1AEEEFC6" xlink:to="loc_us-gaap_AmericasMember_E840553F042D39CDE5EBF8AB1AEE2233" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_EuropeAndMiddleEastMember" xlink:label="loc_nstg_EuropeAndMiddleEastMember_587BC6D73F4372EA90D2F8AB1AEF795C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentGeographicalDomain_0FC07FB91B4E910CA71EF8AB1AEEEFC6" xlink:to="loc_nstg_EuropeAndMiddleEastMember_587BC6D73F4372EA90D2F8AB1AEF795C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AsiaPacificMember" xlink:label="loc_us-gaap_AsiaPacificMember_5E5A851A0FA001725925F8AB1AEFA685" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentGeographicalDomain_0FC07FB91B4E910CA71EF8AB1AEEEFC6" xlink:to="loc_us-gaap_AsiaPacificMember_5E5A851A0FA001725925F8AB1AEFA685" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductOrServiceAxis" xlink:label="loc_us-gaap_ProductOrServiceAxis_712B98970207B912D608F8AB1AEF961A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_1DDC4904711A7416F3B8F8AB1AED436F" xlink:to="loc_us-gaap_ProductOrServiceAxis_712B98970207B912D608F8AB1AEF961A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ProductOrServiceAxis_712B98970207B912D608F8AB1AEF961A" xlink:to="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ProductOrServiceAxis_712B98970207B912D608F8AB1AEF961A" xlink:to="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ProductInstrumentsMember" xlink:label="loc_nstg_ProductInstrumentsMember_D4AD4E41BBD5347B0756F8AB1AEF961E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88" xlink:to="loc_nstg_ProductInstrumentsMember_D4AD4E41BBD5347B0756F8AB1AEF961E" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ProductConsumablesMember" xlink:label="loc_nstg_ProductConsumablesMember_715C5FB1CAEDE4F9F19AF8AB1AF0D3A3" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88" xlink:to="loc_nstg_ProductConsumablesMember_715C5FB1CAEDE4F9F19AF8AB1AF0D3A3" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ProductInVitroDiagnosticKitsMember" xlink:label="loc_nstg_ProductInVitroDiagnosticKitsMember_84ADFA568D0821D1BA96F8AB1AF0BEF0" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88" xlink:to="loc_nstg_ProductInVitroDiagnosticKitsMember_84ADFA568D0821D1BA96F8AB1AF0BEF0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductMember" xlink:label="loc_us-gaap_ProductMember_48D6A35A677FAB5C1030F8AB1AF0A445" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88" xlink:to="loc_us-gaap_ProductMember_48D6A35A677FAB5C1030F8AB1AF0A445" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ServiceMember" xlink:label="loc_nstg_ServiceMember_2FB22CF296DD12168894F8AB1AF02C1F" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88" xlink:to="loc_nstg_ServiceMember_2FB22CF296DD12168894F8AB1AF02C1F" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ProductAndServiceMember" xlink:label="loc_nstg_ProductAndServiceMember_8564FDD8CCC12C0813E0F8AB1AF04815" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88" xlink:to="loc_nstg_ProductAndServiceMember_8564FDD8CCC12C0813E0F8AB1AF04815" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_CollaborationMember" xlink:label="loc_nstg_CollaborationMember_78F8B363AF9D7ADD6962F8AB1AF0F246" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_088DDC581E5EA8C6A862F8AB1AEFFD88" xlink:to="loc_nstg_CollaborationMember_78F8B363AF9D7ADD6962F8AB1AF0F246" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_C3CC3B0C31C403068DBAF8AB1AF11C8D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_9A4EBED548015C672F7DF8AB1AF1949C" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_C3CC3B0C31C403068DBAF8AB1AF11C8D" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/RevenueFromContractsWithCustomersScheduleOfImpactOfChangesInAccountingStandardDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems" xlink:label="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable" xlink:label="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_B8C07B1C7D166829384EF41267349E0C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:to="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_B8C07B1C7D166829384EF41267349E0C" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_6370FE03C097563E4B70F4126734C214" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_B8C07B1C7D166829384EF41267349E0C" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_6370FE03C097563E4B70F4126734C214" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_DF5B1F1D81C38F146251F412673561C3_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_6370FE03C097563E4B70F4126734C214" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_DF5B1F1D81C38F146251F412673561C3_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_DF5B1F1D81C38F146251F412673561C3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_6370FE03C097563E4B70F4126734C214" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_DF5B1F1D81C38F146251F412673561C3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member" xlink:label="loc_us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member_CF4EB6AB7831AC6CB3B0F4126736A48C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_DF5B1F1D81C38F146251F412673561C3" xlink:to="loc_us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member_CF4EB6AB7831AC6CB3B0F4126736A48C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member" xlink:label="loc_us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member_6CB20D87953C9D8E300BF412673617CD" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_DF5B1F1D81C38F146251F412673561C3" xlink:to="loc_us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member_6CB20D87953C9D8E300BF412673617CD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_8D4C1997506F429AEEBCF4126737FA1C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_B8C07B1C7D166829384EF41267349E0C" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_8D4C1997506F429AEEBCF4126737FA1C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_E1E5D13036AD947E618FF412673730A7_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_8D4C1997506F429AEEBCF4126737FA1C" xlink:to="loc_us-gaap_TypeOfAdoptionMember_E1E5D13036AD947E618FF412673730A7_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_E1E5D13036AD947E618FF412673730A7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_8D4C1997506F429AEEBCF4126737FA1C" xlink:to="loc_us-gaap_TypeOfAdoptionMember_E1E5D13036AD947E618FF412673730A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingStandardsUpdate201409Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201409Member_90CE4E20E8A2179605E7F41267382B24" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_E1E5D13036AD947E618FF412673730A7" xlink:to="loc_us-gaap_AccountingStandardsUpdate201409Member_90CE4E20E8A2179605E7F41267382B24" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SalesRevenueNet" xlink:label="loc_us-gaap_SalesRevenueNet_0100916B20D3565422E2F4126738D4DF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:to="loc_us-gaap_SalesRevenueNet_0100916B20D3565422E2F4126738D4DF" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoptionRevenueRecognized" xlink:label="loc_nstg_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoptionRevenueRecognized_C398936C4752548B71C0F425EE36A2C2" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:to="loc_nstg_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoptionRevenueRecognized_C398936C4752548B71C0F425EE36A2C2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LicenseAndServicesRevenue" xlink:label="loc_us-gaap_LicenseAndServicesRevenue_301B68DF3F6BD6FA7906F41267391C41" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:to="loc_us-gaap_LicenseAndServicesRevenue_301B68DF3F6BD6FA7906F41267391C41" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RecognitionOfDeferredRevenue" xlink:label="loc_us-gaap_RecognitionOfDeferredRevenue_30E3ADE5D10089A01D5EF425EF34B4BE" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:to="loc_us-gaap_RecognitionOfDeferredRevenue_30E3ADE5D10089A01D5EF425EF34B4BE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_FEB5EC5A81686255F607F41267391CED" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:to="loc_us-gaap_Revenues_FEB5EC5A81686255F607F41267391CED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_B8A5C71A7EA5077B4BE2F41267393414" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:to="loc_us-gaap_NetIncomeLoss_B8A5C71A7EA5077B4BE2F41267393414" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareBasicAndDiluted" xlink:label="loc_us-gaap_EarningsPerShareBasicAndDiluted_E1549D36203D9D392BA3F4126739E10A" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:to="loc_us-gaap_EarningsPerShareBasicAndDiluted_E1549D36203D9D392BA3F4126739E10A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="loc_us-gaap_DeferredRevenueCurrent_DBF63463CBB4C6A88FF8F412673B24E6" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:to="loc_us-gaap_DeferredRevenueCurrent_DBF63463CBB4C6A88FF8F412673B24E6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_D080FC39A6FBE580D2A4F412673CE967" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_EA964687EDAA032F5870F4126738D949" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_D080FC39A6FBE580D2A4F412673CE967" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/RevenueFromContractsWithCustomersTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/ShortTermInvestments" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/ShortTermInvestmentsAdditionalInformationDetail" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/ShortTermInvestmentsAvailableForSaleSecuritiesDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_814D9224D02B1079365AF1AE2060CE7E" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_1F9142E69C105D31B629F1AE20601635" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_814D9224D02B1079365AF1AE2060CE7E" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_1F9142E69C105D31B629F1AE20601635" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_447DC83A60BFC999CC94F1AE20603C41" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_1F9142E69C105D31B629F1AE20601635" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_447DC83A60BFC999CC94F1AE20603C41" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_81DCAED1AE56C365B333F1AE2060F2E2_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_447DC83A60BFC999CC94F1AE20603C41" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_81DCAED1AE56C365B333F1AE2060F2E2_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_81DCAED1AE56C365B333F1AE2060F2E2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_447DC83A60BFC999CC94F1AE20603C41" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_81DCAED1AE56C365B333F1AE2060F2E2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CorporateDebtSecuritiesMember" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_A40D03FEBB319756891BF1AE20603C37" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_81DCAED1AE56C365B333F1AE2060F2E2" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_A40D03FEBB319756891BF1AE20603C37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_E16833FC407C0D8BDD90F1AE2060983E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_81DCAED1AE56C365B333F1AE2060F2E2" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_E16833FC407C0D8BDD90F1AE2060983E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_0D0053611EF2DC809210F1AE20605230" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_81DCAED1AE56C365B333F1AE2060F2E2" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_0D0053611EF2DC809210F1AE20605230" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_666B9021F6875A459AF8F1AE2060AB71" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_814D9224D02B1079365AF1AE2060CE7E" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_666B9021F6875A459AF8F1AE2060AB71" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_270EB5123F10175D46CFF1AE206066DA" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_814D9224D02B1079365AF1AE2060CE7E" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_270EB5123F10175D46CFF1AE206066DA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_35EFD42249A00B4338CDF1AE20607D6B" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_814D9224D02B1079365AF1AE2060CE7E" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_35EFD42249A00B4338CDF1AE20607D6B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesCurrent" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesCurrent_390CBAA254B7BCB123C5F1AE206032E5" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_814D9224D02B1079365AF1AE2060CE7E" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesCurrent_390CBAA254B7BCB123C5F1AE206032E5" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/ShortTermInvestmentsFairValuesOfAvailableForSaleSecuritiesByContractualMaturityDetail" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/ShortTermInvestmentsSummaryOfInvestmentsInContinuousLossPositionDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_708D7E9DFD587F8F113FF1A0EE8D7B3B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_ADB42D0BF55CC217A0D1F1A0EE8C026C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_708D7E9DFD587F8F113FF1A0EE8D7B3B" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_ADB42D0BF55CC217A0D1F1A0EE8C026C" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D497C7130D7C5B5ECD04F1A0EE8C5E1C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_ADB42D0BF55CC217A0D1F1A0EE8C026C" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D497C7130D7C5B5ECD04F1A0EE8C5E1C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_77066643F031F04F11C4F1A0EE8CA9AD_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D497C7130D7C5B5ECD04F1A0EE8C5E1C" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_77066643F031F04F11C4F1A0EE8CA9AD_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_77066643F031F04F11C4F1A0EE8CA9AD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D497C7130D7C5B5ECD04F1A0EE8C5E1C" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_77066643F031F04F11C4F1A0EE8CA9AD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CorporateDebtSecuritiesMember" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_ECF5D347C0C309B2D5D1F1A0EE8D65E5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_77066643F031F04F11C4F1A0EE8CA9AD" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_ECF5D347C0C309B2D5D1F1A0EE8D65E5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_1F9B52DC17125C390734F1A0EE8D752A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_77066643F031F04F11C4F1A0EE8CA9AD" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_1F9B52DC17125C390734F1A0EE8D752A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_D1417D5E79951796EDC3F1A3778F7AD9" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_77066643F031F04F11C4F1A0EE8CA9AD" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_D1417D5E79951796EDC3F1A3778F7AD9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_8214BA069773258D8269F1A0EE8DC91B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_708D7E9DFD587F8F113FF1A0EE8D7B3B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_8214BA069773258D8269F1A0EE8DC91B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_5038F6F70175B2654352F1A0EE8EFC8C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_708D7E9DFD587F8F113FF1A0EE8D7B3B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_5038F6F70175B2654352F1A0EE8EFC8C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_CC0269DC5C9B8098EA92F1A0EE8EE7D9" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_708D7E9DFD587F8F113FF1A0EE8D7B3B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_CC0269DC5C9B8098EA92F1A0EE8EE7D9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_749AF040A871A57B774EF1A0EE8E3DCC" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_708D7E9DFD587F8F113FF1A0EE8D7B3B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_749AF040A871A57B774EF1A0EE8E3DCC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue_A6CC8D9A931D2E93CA56F1A0EE8ED81D" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_708D7E9DFD587F8F113FF1A0EE8D7B3B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue_A6CC8D9A931D2E93CA56F1A0EE8ED81D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss_D99569AD3672FFA8ED9DF1A0EE8FE3A6" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_708D7E9DFD587F8F113FF1A0EE8D7B3B" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss_D99569AD3672FFA8ED9DF1A0EE8FE3A6" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/ShortTermInvestmentsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.nanostring.com/role/SubsequentEvent" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventLineItems" xlink:label="loc_us-gaap_SubsequentEventLineItems_0510080F2819F2338D1AB48757B874AA" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTable" xlink:label="loc_us-gaap_SubsequentEventTable_DAA936351A01F691CC74B48757B8623B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_0510080F2819F2338D1AB48757B874AA" xlink:to="loc_us-gaap_SubsequentEventTable_DAA936351A01F691CC74B48757B8623B" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_4806194DAD32AE920E0CB48757B85B95" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_DAA936351A01F691CC74B48757B8623B" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_4806194DAD32AE920E0CB48757B85B95" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_6C8E15FB97FB3C1C5EA9B48757B8496C_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_4806194DAD32AE920E0CB48757B85B95" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_6C8E15FB97FB3C1C5EA9B48757B8496C_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_6C8E15FB97FB3C1C5EA9B48757B8496C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_4806194DAD32AE920E0CB48757B85B95" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_6C8E15FB97FB3C1C5EA9B48757B8496C" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.nanostring.com/role/SubsequentEventNarrativeDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventLineItems" xlink:label="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTable" xlink:label="loc_us-gaap_SubsequentEventTable_494D2ABC787778226F95EBD3E29385E0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_us-gaap_SubsequentEventTable_494D2ABC787778226F95EBD3E29385E0" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodAxis" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_F5A3CEBDE280495EB937EBD3E295CE51" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_494D2ABC787778226F95EBD3E29385E0" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_F5A3CEBDE280495EB937EBD3E295CE51" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodDomain" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_B569CC1982D2963F4A9BEBD3E296FBF9_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_F5A3CEBDE280495EB937EBD3E295CE51" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_B569CC1982D2963F4A9BEBD3E296FBF9_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodDomain" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_B569CC1982D2963F4A9BEBD3E296FBF9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_F5A3CEBDE280495EB937EBD3E295CE51" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_B569CC1982D2963F4A9BEBD3E296FBF9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodOneMember" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodOneMember_89BA2806A150117A30B4EBD3E2969B7C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_B569CC1982D2963F4A9BEBD3E296FBF9" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodOneMember_89BA2806A150117A30B4EBD3E2969B7C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodTwoMember" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodTwoMember_63DD0DABC112E0183650EBD3E298E316" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_B569CC1982D2963F4A9BEBD3E296FBF9" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodTwoMember_63DD0DABC112E0183650EBD3E298E316" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_CD933C3F05D26655B071EBD3E2993E9D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_494D2ABC787778226F95EBD3E29385E0" xlink:to="loc_us-gaap_DebtInstrumentAxis_CD933C3F05D26655B071EBD3E2993E9D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_09312CCC6B84B5224781EBD3E29AD30C_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_CD933C3F05D26655B071EBD3E2993E9D" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_09312CCC6B84B5224781EBD3E29AD30C_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_09312CCC6B84B5224781EBD3E29AD30C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_CD933C3F05D26655B071EBD3E2993E9D" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_09312CCC6B84B5224781EBD3E29AD30C" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_CRGServicingLLCAmendedAndRestatedLoanAgreementMember" xlink:label="loc_nstg_CRGServicingLLCAmendedAndRestatedLoanAgreementMember_5E31573D70E794ADF287EBD3E29A98A5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_09312CCC6B84B5224781EBD3E29AD30C" xlink:to="loc_nstg_CRGServicingLLCAmendedAndRestatedLoanAgreementMember_5E31573D70E794ADF287EBD3E29A98A5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_AD54D4579F3D91144781EBD3E29A2AAE" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_494D2ABC787778226F95EBD3E29385E0" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_AD54D4579F3D91144781EBD3E29A2AAE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_ED5139E246EE027D667DEBD3E29BFF76_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_AD54D4579F3D91144781EBD3E29A2AAE" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_ED5139E246EE027D667DEBD3E29BFF76_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_ED5139E246EE027D667DEBD3E29BFF76" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_AD54D4579F3D91144781EBD3E29A2AAE" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_ED5139E246EE027D667DEBD3E29BFF76" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_PublicStockOfferingMember" xlink:label="loc_nstg_PublicStockOfferingMember_FAA540916D2E633DF21AEBD3E29BCAB8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_ED5139E246EE027D667DEBD3E29BFF76" xlink:to="loc_nstg_PublicStockOfferingMember_FAA540916D2E633DF21AEBD3E29BCAB8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_0D628504CE98540496AFEBD3E29CC469" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_494D2ABC787778226F95EBD3E29385E0" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_0D628504CE98540496AFEBD3E29CC469" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_ACF571BD6B55C312C245EBD3E29CB237_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_0D628504CE98540496AFEBD3E29CC469" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_ACF571BD6B55C312C245EBD3E29CB237_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_ACF571BD6B55C312C245EBD3E29CB237" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_0D628504CE98540496AFEBD3E29CC469" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_ACF571BD6B55C312C245EBD3E29CB237" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember_8466827C8DB3628CED3EEBD3E29C324E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_ACF571BD6B55C312C245EBD3E29CB237" xlink:to="loc_us-gaap_SubsequentEventMember_8466827C8DB3628CED3EEBD3E29C324E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_2FF1546D8C553DEC536FEBD3E29DAE48" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_2FF1546D8C553DEC536FEBD3E29DAE48" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ProceedsFromIssuanceOfLongTermDebtNetOfDebtExtinguishmentAndIssuanceCost" xlink:label="loc_nstg_ProceedsFromIssuanceOfLongTermDebtNetOfDebtExtinguishmentAndIssuanceCost_2173AE5A0360F644D68BEBD7DAA75F1E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_nstg_ProceedsFromIssuanceOfLongTermDebtNetOfDebtExtinguishmentAndIssuanceCost_2173AE5A0360F644D68BEBD7DAA75F1E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt_144C56975C3BC9E43A4EEBD8213E413F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt_144C56975C3BC9E43A4EEBD8213E413F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LoansPayable" xlink:label="loc_us-gaap_LoansPayable_EBD82329B8A90205572AEBD3E2A0136D" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_us-gaap_LoansPayable_EBD82329B8A90205572AEBD3E2A0136D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_FE713C6125436429485FEBDA17EEE417" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_FE713C6125436429485FEBDA17EEE417" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_26637983470B8AE9F29DEBDA71F9268D" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_26637983470B8AE9F29DEBDA71F9268D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtPercentageBearingFixedInterestRate" xlink:label="loc_us-gaap_LongTermDebtPercentageBearingFixedInterestRate_19743BD42AB279D07C7BEBD3E2A19014" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_us-gaap_LongTermDebtPercentageBearingFixedInterestRate_19743BD42AB279D07C7BEBD3E2A19014" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_DeferredPaymentObligationAccruedInterestRate" xlink:label="loc_nstg_DeferredPaymentObligationAccruedInterestRate_0288279F2A7278E01BF7EBD3E2A1701D" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_nstg_DeferredPaymentObligationAccruedInterestRate_0288279F2A7278E01BF7EBD3E2A1701D" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_DebtInstrumentInterestDeferralPeriod" xlink:label="loc_nstg_DebtInstrumentInterestDeferralPeriod_5350D2EEB855C44CDB56EBD3E2A1EF42" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_nstg_DebtInstrumentInterestDeferralPeriod_5350D2EEB855C44CDB56EBD3E2A1EF42" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_UpfrontFeeOfAggregatePrincipalAmountPercentage" xlink:label="loc_nstg_UpfrontFeeOfAggregatePrincipalAmountPercentage_A40FC22AAC9998F22857EBD3E2A17C5A" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_nstg_UpfrontFeeOfAggregatePrincipalAmountPercentage_A40FC22AAC9998F22857EBD3E2A17C5A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityCommitmentFeePercentage" xlink:label="loc_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_0B2B142CCC95817447D2EBD3E2A20D2D" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_0B2B142CCC95817447D2EBD3E2A20D2D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:label="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_AC654ECB83B7F958A9C3EBD3E2A39D0F" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_AC654ECB83B7F958A9C3EBD3E2A39D0F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_17569C740B42F100A4CDEBD3E2A35204" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_17569C740B42F100A4CDEBD3E2A35204" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRightsFutureDrawPercentageOfDilutedSharesOutstanding" xlink:label="loc_nstg_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRightsFutureDrawPercentageOfDilutedSharesOutstanding_A7DE53C5621D9D183228EBD3E2A485E0" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_nstg_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRightsFutureDrawPercentageOfDilutedSharesOutstanding_A7DE53C5621D9D183228EBD3E2A485E0" xlink:type="arc" />
    <link:loc xlink:href="nstg-20180930.xsd#nstg_ClassofWarrantorRightExercisePriceofWarrantsorRightsPercentagePremiumToAverageClosingTradingPrice" xlink:label="loc_nstg_ClassofWarrantorRightExercisePriceofWarrantsorRightsPercentagePremiumToAverageClosingTradingPrice_D2FABF89D4078C91BD3EEBD3E2A4D808" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_3099566C61209545B9D3EBD3E29D44F2" xlink:to="loc_nstg_ClassofWarrantorRightExercisePriceofWarrantsorRightsPercentagePremiumToAverageClosingTradingPrice_D2FABF89D4078C91BD3EEBD3E2A4D808" xlink:type="arc" />
  </link:definitionLink>
</link:linkbase>
