1 [U] a hard yellow metal that is a mixture of two other metals (copper)and(zinc) 黄铜: brass buttons on a uniform 制服上的黄铜扣子

2 [sing] [with.sop] the group of musical instruments that are made of brass 铜管乐器: the brass section in an orchestra 管弦乐队中的铜管乐部份