不贰 bù'èr undivided Origin Definitions Defs Strokes Stroke Words Sentences Sents 不 bù adverb not Negative adverb used before verbs, adjectives, and other adverbs to indicate negation; also used as a bound-form prefix to form terms with opposite meanings贰 貳 èr to betray (bound form) to be disloyal; to betray; to have a change of heart