negligée

from Wiktionary, Creative Commons Attribution/Share-Alike License

• n. A light women's gown.
• n. A loose women's dressing-gown, especially when lacy or revealing; a nightgown.

from The Century Dictionary and Cyclopedia

• n. Easy and unceremonious dress in general: as, she appeared in negligée.
• n. A form of loose gown worn by women in the eighteenth century.
• n. See negligée necklace, below.
• Carelessly arranged or attired; unceremoniously dressed; careless.