1 (formal 正式) a thing that goes together well with sth else 互相配合的事物；补足物: Ice cream is the perfect complement to this dessert. 冰淇淋是这个甜点的最佳搭配。

2 the total number that makes a group complete 组成整体的数量；足额: Without a full complement of players, the team will not be able to take part in the match. 没有完整的阵容，这队伍就不能出赛。

3 (grammar语法) a word or words, especially a noun or adjective, used after a verb such as ‘be’ or ‘become’ and describing the subject of that verb 补语（尤指在动词如be或become之后用以描述主语的名词或形容词）: In ‘He's friendly’ and ‘He's a fool’, ‘friendly’ and ‘fool’ are complements. 在He's friendly和He's a fool中，friendly和fool都是补语。