stag party
A groom's outing with his male friends before his wedding; a bachelor party. Mark knew that his stag party had gotten out of control when the police arrived.
stag party
A social gathering for men exclusively, often involving entertainment considered unsuitable for women. For example, They wanted to give him a stag party before the wedding but John wasn't interested. This idiom uses stag in the sense of "a man unaccompanied by a woman." [c. 1850]
stag-party
n. a party for men only. (Thought to be raunchy.) They hired a stripper for the stag-party—you know, the kind that jumps out of a cake.