noun
source language; language being translated from
Technical term used in translation studies and localization to refer to the language from which a text is translated.
翻訳元言語が英語の場合、日本語への翻訳は比較的容易だ。
When the source language is English, translation into Japanese is relatively easy.
このツールは翻訳元言語を自動的に検出します。
This tool automatically detects the source language.