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}]
Source: WordNet® 2.0