counter
counter for languages
Attaches to a number to count how many languages someone speaks, understands, or a text is written in. The counter part is read か.
彼は3か国語を話せる。
He can speak three languages.
この書類は5か国語に翻訳されている。
This document has been translated into five languages.
か国 is a counter for countries, while か国語 counts languages.
The counter か derives from the kanji 箇 (ka), a generic counter. The spelling ヶ is a simplified form of 箇, and か is its hiragana representation. 国語 means 'national language' or 'language'.