Source : Webster's Revised Unabridged Dictionary (1913)

Penis \Pe"nis\ (p[=e]"n[i^]s), n. [L.] (Anat.)
   The male member, or organ of generation.

Source : WordNet®

penis
     n : the male organ of copulation (`member' is a euphemism) [syn:
          {phallus}, {member}]
     [also: {penes} (pl)]