The Collaborative International Dictionary of English v.0.48:

Metatarsus \Met`a*tar"sus\, n.; pl. Metatarsi. [NL. See
   Meta-, and Tarsus.] (Anat.)
   That part of the skeleton of the hind or lower limb between
   the tarsus and phalanges; metatarse. It consists, in the
   human foot, of five bones. See Illustration in Appendix.
   [1913 Webster]

WordNet (r) 3.0 (2006):

metatarsus
    n 1: the skeleton of the human foot between the toes and the
         tarsus; the corresponding part of the foot in birds or of
         the hind foot in quadrupeds