sex

Sex is an act done by a male and a female (in this case there is sometimes an intent to make babies) or with just two men or women.

Example: Most men in our survey say they definitely would not have sex with a new partner without using a condom.

A person or animal's sex is male, female, or both.

Example: She had not had any male friends during her early life and now found it difficult to talk to members of the opposite sex.