expression, noun
language isolate
A natural language with no demonstrable genealogical relationship to other languages. Used in linguistics.
バスク語はヨーロッパで唯一の孤立した言語とされる。
Basque is considered the only language isolate in Europe.
日本語は孤立した言語かどうか議論がある。
There is debate over whether Japanese is a language isolate.
孤立語 (isolating language) refers to a language with little or no morphology, where each word tends to be a single morpheme. 孤立した言語 (language isolate) refers to a language with no known relatives.
Compound of 孤立 (isolated) + した (past attributive form of する) + 言語 (language). The term is a direct translation of the English 'language isolate'.