(こういしつ)

こういしつ
noun
changing room; locker room
building
1. changing room; locker room; dressing room
A room where people change clothes, found in gyms, pools, sports facilities, and stores.
更衣室(こういしつ)着替(きが)えてください
Please change in the changing room.
The pool changing rooms are separate for men and women.
更衣室(こういしつ)ロッカーある
There are lockers in the changing room.

更衣室(こういしつ) is the room where you change into or out of sports clothes, a uniform, or a swimsuit. Formation: 更衣(こうい) 'changing clothes' + (しつ) 'room'.

Where you find one: a ジム, a プール, スポーツ施設(しせつ) of any kind, and the staff areas of workplaces where a uniform is worn.

Collocations

Do not use it of a shop: trying on clothes before buying happens in a 試着室(しちゃくしつ) (fitting room). A 控室(ひかえしつ) is a room to wait in, not to change in.