Meaning of source language

source' lan"guage

Pronunciation: [key]
  1. the language in which a text appears that is to be translated into another language. Cf.(def. 1).
  2. a language, usually the learner's native language, that is a source of interference in learning another language. Cf.(def. 2).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.