不透气 bútòuqì airtight Definitions Defs Origin 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透气 透氣 tòuqì verb + noun to ventilate To allow air to flow freely; to be breathable, as in the case of fabric or a room.