A cikin ilimin lissafi, jimlar kai tsaye gini ne wanda ke haɗa abubuwa biyu ko fiye da na lissafi zuwa wani abu mafi girma. Jimlar kai tsaye yawanci ana nuna ta ta alamar ⊕ ko ⊕j, kuma ana iya siffanta ta a wurare daban-daban, gami da: kuma W shine sararin sararin samaniya V ⊕ W wanda ya ƙunshi dukkan nau'i-nau'i da aka yi oda (v, w), inda v shine kashi na V kuma w shine kashi na W. A cikin abstract algebra, jimlar rukunoni biyu G da H ita ce rukunin G ⊕ H wanda ya ƙunshi dukkan nau'i-nau'i da aka yi oda (g, h), inda g shine sigar G kuma h shine kashi na H. A cikin ilimin kimiyyar yanayi, jimlar kai tsaye na wurare biyu na topological X da Y ita ce sararin samaniya X ⊕ Y wanda ya ƙunshi dukkan nau'i-nau'i da aka yi oda (x, y), inda x ya kasance sigar X da y. wani kashi ne na Y, wanda aka baiwa samfurin topology.Gaba ɗaya, jimlar kai tsaye na abubuwa da yawa A1, A2, ..., An ana nunawa ta A1 ⊕ A2 ⊕ ... ⊕ An kuma an ayyana shi azaman saitin duk n-tuples da aka yi oda (a1, a2, ..., an), inda ai shine kashi na Ai don i = 1, 2, ..., n . Hakanan ana iya haɗa jimlar kai tsaye tare da ayyuka masu dacewa, kamar ƙari, ninkawa, ko haɗawa, dangane da mahallin da aka yi amfani da shi.