A waiting or duty room where people or staff stand by or wait for their turn; commonly used in hospitals, event venues, or workplaces.
患者は受付で番号をもらって待機室で待っていた。
The patient received a number at reception and waited in the waiting room.
出演者は出番前に控え室ではなく待機室に集められた。
The performers were gathered in the waiting room rather than the green room before their turns.
新人スタッフは交代時間まで待機室で待機していた。
The new staff waited in the duty room until their shift change.