Source : Webster's Revised Unabridged Dictionary (1913)

Navel \Na"vel\ (n[=a]"v'l), n. [AS. nafela, fr. nafu nave; akin
   to D. navel, G. nabel, OHG. nabolo, Icel. nafli, Dan. navle,
   Sw. nafle, L. umbilicus, Gr. 'omfalo`s, Skr. n[=a]bh[=i]la.
   [root]260. See {Nave} hub, and cf. {Omphalic}, {Nombril},
   {Umbilical}.]
   1. (Anat.) A mark or depression in the middle of the abdomen;
      the umbilicus. See {Umbilicus}.

Source : WordNet®

navel
     n 1: scar where the umbilical cord was attached [syn: {umbilicus},
           {bellybutton}, {omphalos}, {omphalus}]
     2: the center point or middle of something [syn: {navel point}]