Ma'anar ƙamus na kalmar "fassarar lamuni" tana nufin tsarin fassara kalma ko jimla daga wannan harshe zuwa wani ta hanyar rarraba ta zuwa sassan sassanta sannan a fassara kowane bangare daban. Wanda kuma aka sani da "calque," wannan tsari ya ƙunshi aron kalmomi ko jimloli daga harshe ɗaya da ƙirƙirar sabuwar magana ko kalma a cikin wani harshe mai ma'ana iri ɗaya. Fassarar da aka samu na iya zama mai banƙyama ko ta zahiri, amma galibi ana amfani da ita a fannoni na musamman ko cikin harsunan da babu wata kalma ko jimla makamanciyarta.Misali, kalmar Turanci "Blue blood" fassarar aro ce daga kalmar Mutanen Espanya "sangre azul," wanda ke nufin ajin daraja wanda jijiyoyinsu suka fito shudi ta fatar fatarsu. Hakazalika, kalmar Ingilishi "to hasarar fuska" fassarar aro ce daga kalmar Sinanci "diu lien," wanda ke nufin rasa matsayin mutum ko mutunci.