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nightclothes; nightwear; sleepwear; pyjamas; pajamas; nightgown; nightdress
入院中は病院の寝巻きを着ることになる。
During hospitalization, you wear the hospital's pajamas.
寒いので厚手の寝巻きに着替えた。
It was cold, so I changed into thick pajamas.
旅館で用意された寝巻きは浴衣だった。
The sleepwear provided at the inn was a yukata.