, also called "sleepwear", "nightclothes", or "nightdress", is clothing
designed to be worn while sleeping. It is generally worn otherwise only in the company of those one knows well. Some people do not use nightwear at all, preferring to sleep nude or in some kind of underwear
. Some nightwear usage is seasonal, i.e. some persons only wear nightwear in winter.
Examples of types of items of nightwear include