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waiting room; anteroom; antechamber; green room
出演者は控室で本番を待っていた。
The performers were waiting in the green room.
控室でリラックスしてから面接に臨んだ。
I relaxed in the waiting room before the interview.
選手たちは控室で作戦を確認した。
The players confirmed their strategy in the waiting room.