Kalmar "jini na kwan fitila" tana nufin jigon jini da ke ba wa kwan fitilar azzakari da jini mai iskar oxygen. Kwan fitila na azzakari shi ne ƙaƙƙarfa, tsari mai bulbous a gindin azzakari wanda ke cikin kogon ƙashin ƙugu. Jijiyoyin kwan fitila wani muhimmin bangare ne na tsarin jijiyoyin jini na tsarin haihuwa na namiji kuma yana taka muhimmiyar rawa wajen saukaka tsayuwa.
