Cottaging is a gay slang term, originating from the United Kingdom, referring to anonymous sex between men in a public lavatory (a "cottage" or "tea-room"), or cruising for sexual partners with the intention of having sex elsewhere. The term has its roots in self-contained English toilet blocks resembling small cottages in their appearance; in the English cant language of Polari this became a double entendre by gay men referring to sexual encounters. See also gay beat in Australian English.

The word "cottage", usually meaning a small, cosy, countryside home, is documented as having been in use during the Victorian era to refer to a public toilet and by the 1960s its use in this sense had become an exclusively homosexual slang term. This usage is predominantly British, though the term is occasionally used with the same meaning in other parts of the world. Among gay men in the United States, lavatories used for this purpose are called tea rooms.