The Collaborative International Dictionary of English v.0.48:
housecoat \housecoat\ n. a loose dressing gown for women. Syn: negligee, neglige, peignoir, wrapper. [WordNet 1.5]WordNet (r) 3.0 (2006):
housecoat n 1: a loose dressing gown for women [syn: negligee, neglige, peignoir, wrapper, housecoat]