endangered language
A language at risk of falling out of use as its speakers die out or shift to speaking other languages. Used in linguistics and language preservation contexts.
UNESCO publishes a list of the world's endangered languages.
In this region, efforts are underway to protect endangered languages.
少数言語 (minority language) refers to a language spoken by a small population, which may or may not be endangered. 危機言語 specifically implies the language is at risk of extinction.
消滅危機言語 is a more explicit term for 'endangered language', literally 'language in danger of extinction'. 危機言語 is a shorter, commonly used equivalent.
endangered language; seriously endangered language
Compound of 危機 (kiki, 'crisis') and 言語 (gengo, 'language'). A modern term reflecting global awareness of language endangerment.