set of clothing for sleeping

Pajamas (pyjamas in the United Kingdom) are loose clothes that people wear while they are sleeping. Pyjamas usually include trousers and a shirt. Pyjamas are often made of cotton. They are usually worn without underwear. The word comes from Hindi: पजामा, Pajāmā; Persian: پايجامه. Pajamas are often worn without underwear.

A girl (and her doll) wearing pyjamas.