noun
stag party; bachelor party
A party for a man who is about to get married, typically attended only by men. The term is a direct loan from English and is used in modern Japanese contexts.
来週、友達のスタッグパーティーを開く予定だ。
We're planning to throw a stag party for a friend next week.
スタッグパーティーでは新郎をからかうのが恒例だ。
It's customary to tease the groom at a stag party.