The Collaborative International Dictionary of English v.0.48:

neglige \neg`li*ge"\, negligee
\neg`li*gee"\(n[e^]g`l[i^]*zh[=a]"; F. n[asl]`gl[-e]`zh[asl]"),
   n. [Also spelled neglig['e] and neglig['e]e.][F.
   n['e]glig['e], fr. n['e]gliger to neglect, L. negligere. See
   Neglect.]
   1. An easy, unceremonious attire; undress.
      [1913 Webster]

   2. A kind of loose, flowing dressing gown worn by women,
      usually made of sheer fabric.

   Syn: negligee, peignoir.
        [1913 Webster + PJC]

WordNet (r) 3.0 (2006):

negligee
    n 1: a loose dressing gown for women [syn: negligee,
         neglige, peignoir, wrapper, housecoat]