From WordNet (r) 2.0 (August 2003) [wn]:
fundament
n 1: the fundamental assumptions from which something is begun or
developed or calculated or explained; "the whole
argument rested on a basis of conjecture" [syn: basis,
base, foundation, groundwork, cornerstone]
2: the fleshy part of the human body that you sit on; "he
deserves a good kick in the butt"; "are you going to sit
on your fanny and do nothing?" [syn: buttocks, nates,
arse, butt, backside, bum, buns, can,
hindquarters, hind end, keister, posterior,
prat, rear, rear end, rump, stern, seat,
tail, tail end, tooshie, tush, bottom, behind,
derriere, fanny, ass]
3: lowest support of a structure; "it was built on a base of
solid rock"; "he stood at the foot of the tower" [syn:
foundation, base, foot, groundwork,
substructure, understructure]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Fundament \Fun"da*ment\, n. [OE. fundament, fundement,
fondement, OF. fundement, fondement, F. fondement, fr. L.
fundamentum foundation, fr. fundare to lay the bottom, to
found, fr. fundus bottom. See Fund.]
1. Foundation. [Obs.] --Chaucer.
[1913 Webster]
2. The part of the body on which one sits; the buttocks;
specifically (Anat.), the anus. --Hume.
[1913 Webster]