negligee
noun
[ ˈnɛɡlɪʒeɪ ]
• a woman's light dressing gown, typically made of a filmy, soft fabric.
• "a black silk negligee"
Origin:
mid 18th century (denoting a kind of loose gown worn by women): from French, literally ‘given little thought or attention’, feminine past participle of négliger ‘to neglect’.