i Register
In some senses, nightie is marked as informal. Watch for register when choosing this word.
noun
A woman's nightgown or nightdress for wearing to bed.
I was too embarrassed to answer the door in my nightie.
The clip shows the 67-year-old enfant terrible of French letters in pyjamas lying on a bed next to a woman in a nightie, smoking and laughing.
phrase
Alternative form of nighty (“good night”).