Source : Webster's Revised Unabridged Dictionary (1913)

Pithecanthropus \Pith`e*can*thro"pus\, n. [NL.; Gr. ? ape + ?
   man.]
   1. A hypothetical genus of primates intermediate between man
      and the anthropoid apes.

Source : WordNet®

Pithecanthropus
     n : former genus of primitive apelike men now Homo erectus [syn:
          {Pithecanthropus erectus}, {genus Pithecanthropus}]