1 [U] the state of being either male or female 性别: Applications are welcome from anyone, regardless of sex or race. 欢迎任何人申请，不论性别、种族。Do you mind what sex your baby is? 你想生男还是生女？ [SYN] gender 同义词为gender

2 [C] one of the two groups consisting of all male people or all female people 男性；女性: the male/female sex 男性；女性He's always found it difficult to get on with the opposite sex (= women). 他总觉得难以和异性相处。

3 (formal 正式coitusintercoursesexual intercourse) [U] the physical act in which the sexual organs of two people touch and which can result in a woman having a baby 性交: to have sex with somebody 与某人性交sex education in schools 学校的性教育