<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:01a178b2-c8bf-7b60-85fa-4783dff71964,g:f5e5d9c8-99e1-4ee1-810a-c2383e1b40fb-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://blackberry.com/role/Cover" xlink:type="simple" xlink:href="bbry-20261027.xsd#Cover"/>
  <link:definitionLink xlink:role="http://blackberry.com/role/Cover" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable_01a178b2-c8bf-7822-8b39-f3b08a2d73b9" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_DocumentInformationTable_01a178b2-c8bf-7822-8b39-f3b08a2d73b9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityListingsExchangeAxis_01a178b2-c8bf-78e2-9aad-b59abe40e657" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityListingsExchangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_DocumentInformationTable_01a178b2-c8bf-7822-8b39-f3b08a2d73b9" xlink:to="loc_dei_EntityListingsExchangeAxis_01a178b2-c8bf-78e2-9aad-b59abe40e657" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_ExchangeDomain_01a178b2-c8bf-78e2-9aad-b59abe40e657_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_ExchangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_EntityListingsExchangeAxis_01a178b2-c8bf-78e2-9aad-b59abe40e657" xlink:to="loc_dei_ExchangeDomain_01a178b2-c8bf-78e2-9aad-b59abe40e657_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_ExchangeDomain_01a178b2-c8bf-7b4a-bdb9-66c0dea0cc41" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_ExchangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_EntityListingsExchangeAxis_01a178b2-c8bf-78e2-9aad-b59abe40e657" xlink:to="loc_dei_ExchangeDomain_01a178b2-c8bf-7b4a-bdb9-66c0dea0cc41" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exch_XNYS_01a178b2-c8bf-79ad-a35f-a8037ecb51a9" xlink:href="https://xbrl.sec.gov/exch/2026/exch-2026.xsd#exch_XNYS"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_ExchangeDomain_01a178b2-c8bf-7b4a-bdb9-66c0dea0cc41" xlink:to="loc_exch_XNYS_01a178b2-c8bf-79ad-a35f-a8037ecb51a9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_01a178b2-c8bf-7576-b0cf-cfdf93191f75" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_DocumentType_01a178b2-c8bf-7576-b0cf-cfdf93191f75" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_01a178b2-c8bf-7a47-84eb-2cf734e19955" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentPeriodEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_DocumentPeriodEndDate_01a178b2-c8bf-7a47-84eb-2cf734e19955" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_01a178b2-c8bf-71b8-92cb-0b9e71840bbd" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityRegistrantName_01a178b2-c8bf-71b8-92cb-0b9e71840bbd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_01a178b2-c8bf-7e62-8346-db9f4b84b893" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityIncorporationStateCountryCode_01a178b2-c8bf-7e62-8346-db9f4b84b893" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_01a178b2-c8bf-7fd7-b6a0-52372636daaa" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityFileNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityFileNumber_01a178b2-c8bf-7fd7-b6a0-52372636daaa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_01a178b2-c8bf-70ce-9a85-fbd0d4c18b2d" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityTaxIdentificationNumber_01a178b2-c8bf-70ce-9a85-fbd0d4c18b2d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_01a178b2-c8bf-7ba5-9867-13b9bc71c2a5" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityAddressAddressLine1_01a178b2-c8bf-7ba5-9867-13b9bc71c2a5" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_01a178b2-c8bf-7c56-9c2d-fb193a308347" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityAddressCityOrTown_01a178b2-c8bf-7c56-9c2d-fb193a308347" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_01a178b2-c8bf-7122-a258-f4d37d97538f" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityAddressStateOrProvince_01a178b2-c8bf-7122-a258-f4d37d97538f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCountry_01a178b2-c8bf-754c-8504-bbb668136add" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressCountry"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityAddressCountry_01a178b2-c8bf-754c-8504-bbb668136add" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_01a178b2-c8bf-7334-9530-be6adc1e4a04" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityAddressPostalZipCode_01a178b2-c8bf-7334-9530-be6adc1e4a04" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_01a178b2-c8bf-78f0-9639-a961915adf26" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_CityAreaCode_01a178b2-c8bf-78f0-9639-a961915adf26" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_01a178b2-c8bf-7c67-80d1-4ae7e1438a94" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_LocalPhoneNumber_01a178b2-c8bf-7c67-80d1-4ae7e1438a94" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_01a178b2-c8bf-7a8d-bee8-e5d46fa9a428" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_WrittenCommunications"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_WrittenCommunications_01a178b2-c8bf-7a8d-bee8-e5d46fa9a428" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_01a178b2-c8bf-7609-80cc-331a3b503202" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_SolicitingMaterial"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_SolicitingMaterial_01a178b2-c8bf-7609-80cc-331a3b503202" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_01a178b2-c8bf-7734-a0b7-4f0bb458f603" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_PreCommencementTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_PreCommencementTenderOffer_01a178b2-c8bf-7734-a0b7-4f0bb458f603" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_01a178b2-c8bf-7191-a1a9-514962c6ea95" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_01a178b2-c8bf-7191-a1a9-514962c6ea95" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_01a178b2-c8bf-7b71-91cf-239c628bdf40" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityEmergingGrowthCompany_01a178b2-c8bf-7b71-91cf-239c628bdf40" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_01a178b2-c8bf-7635-b042-353aff1b559a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCentralIndexKey"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_EntityCentralIndexKey_01a178b2-c8bf-7635-b042-353aff1b559a" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_01a178b2-c8bf-73b0-a2a6-585cd9e346f1" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_AmendmentFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_AmendmentFlag_01a178b2-c8bf-73b0-a2a6-585cd9e346f1" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12gTitle_01a178b2-c8bf-74c5-9cd9-42322625b7f0" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_Security12gTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_Security12gTitle_01a178b2-c8bf-74c5-9cd9-42322625b7f0" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_01a178b2-c8bf-790e-8ee6-16b68ee0ec4c" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_TradingSymbol_01a178b2-c8bf-790e-8ee6-16b68ee0ec4c" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_01a178b2-c8bf-7ad8-b2cd-178fa2cd51df" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_01a178b2-c8bf-7f4d-8850-57c410d601fd" xlink:to="loc_dei_SecurityExchangeName_01a178b2-c8bf-7ad8-b2cd-178fa2cd51df" xlink:type="arc" order="22"/>
  </link:definitionLink>
</link:linkbase>
