WordNet (r) 3.0 (2006):

unclad
    adj 1: having removed clothing [syn: unappareled, unattired,
           unclad, undressed, ungarbed, ungarmented]

Moby Thesaurus II by Grady Ward, 1.0:

26 Moby Thesaurus words for "unclad":
   clothesless, decollete, disrobed, en deshabille, garbless,
   garmentless, half-clothed, in dishabille, low-cut, naked, nude,
   nudish, raimentless, raw, stark-naked, strapless, stripped,
   topless, unattired, uncased, unclothed, undraped, undressed,
   ungarbed, ungarmented, unrobed