密不透风 mìbùtòufēng airtight Definitions Defs Origin Strokes Stroke Words Sentences Sents 密 mì adjectivenoun dense dense; thick; closely spaced; packed together不 bu particle [potential] Used between a verb and its result to show that the action cannot achieve that result; used as the negative form of the 得 de potential construction透风 透風 tòufēng to ventilate to let air pass through; to be drafty; to ventilate