助動詞

(Japanese or Korean grammar) a class of 付属語 (fuzokugo, “bound forms”) that attach to 用言 (yōgen, “inflected words”) to add additional grammatical functions, such as tense, aspects, mood, evidentiality, etc.; strictly speaking, they must have verb-like inflection; broadly speaking, they include forms with adjective-like inflection and uninflected particles

(non-Japanese and non-Korean grammar) an auxiliary verb