A negligee is a very light, pretty robe a woman wears over a nightdress. It is usually thin — silk, chiffon, or lace — and it is meant to look soft, not to keep you warm. A thick winter dressing gown is a different thing, even if shops lump them together. You meet the word in lingerie shops, films, and older books more than in ordinary talk; it still feels a little French and a little fancy. People sometimes stretch it to mean any pretty nightclothes, though actually the older, tighter sense is the thin coat worn over the nightdress, not the nightdress itself.

薄紗睡袍。台灣店裡多半只寫「睡袍」；較厚、用來保暖的那件比較常叫晨衣或浴袍。