sex

sex

I

sex¹ S1 W2 AC /seks/ noun1. [uncountable] the physical activity that two people do together in order to produce babies, or for pleasure ⇨ sexual:
    All you see on TV is sex and violence these days.
    They had sex in the back seat of his car.
    She no longer wanted to have sex with him.
    premarital sex/sex before marriage (=sex happening before marriage)
    the dangers of casual sex (=having sex with someone without intending to have a serious relationship)
    safe sex (=ways of having sex that reduce the spread of sexual diseases)
    unprotected sex (=sex without a condom)
2. [uncountable] whether a person, plant, or animal is male or female:
    Put your name and sex at the top of the form.
3. [countable] all men, considered as a group, or all women, considered as a group ⇨ sexual:
    He found it difficult to talk to members of the opposite sex (=people that were not his own sex).
    People of both sexes (=both men and women) buy her records.
4. single-sex school/college etc British English a school etc for either males or females, but not for both together

II

sex² verb [transitive] technicalto find out whether an animal is male or female
     
sex something ↔ up phrasal verb informal
  to change something in order to make it more exciting:
    The organization is trying to sex up its image.