From WordNet (r) 3.0 (2006) [wn]:
thong
n 1: leather strip that forms the flexible part of a whip [syn:
lash, thong]
2: underpants resembling a G-string; worn by women especially
under very tight pants; "she wore thongs in her quest for the
callipygian ideal"
3: a thin strip of leather; often used to lash things together
4: minimal clothing worn by stripteasers; a narrow strip of
fabric that covers the pubic area, passes between the thighs,
and is supported by a waistband [syn: G-string, thong]
5: a backless sandal held to the foot by a thong between the big
toe and the second toe [syn: flip-flop, thong]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Thong \Thong\, n. [OE. thong, [thorn]wong, thwang, AS.
[thorn]wang; akin to Icel. [thorn]vengr a thong, latchet.
[root]57. Cf. Twinge.]
A strap of leather; especially, one used for fastening
anything.
[1913 Webster]
And nails for loosened spears, and thongs for shields,
provide. --Dryden.
[1913 Webster]
Thong seal (Zool.), the bearded seal. See the Note under
Seal.
[1913 Webster]