bất biến

== Vietnamese == === Etymology === Sino-Vietnamese word from 不變, composed of 不 (“not”) and 變 (“change”). === Pronunciation === (Hà Nội) IPA(key): [ʔɓət̚˧˦ ʔɓiən˧˦] (Huế) IPA(key): [ʔɓək̚˦˧˥ ʔɓiəŋ˦˧˥] (Saigon) IPA(key): [ʔɓək̚˦˥ ʔɓiəŋ˦˥] === Adjective === bất biến (chiefly grammar) invariable