The Collaborative International Dictionary of English v.0.48:

loincloth \loincloth\ n.
   A cloth covering for the loins, worn around the hips; --
   sometimes worn in tropical areas as the only article of
   clothing.

   Syn: breechcloth, breechclout, G-string.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

loincloth
    n 1: a garment that provides covering for the loins [syn:
         breechcloth, breechclout, loincloth]