The Collaborative International Dictionary of English v.0.48:

Tarsus \Tar"sus\, n.; pl. Tarsi. [NL., fr. Gr. ? the flat of
   the foot, the edge of the eyelid. Cf. 2d Tarse.]
   1. (Anat.)
      (a) The ankle; the bones or cartilages of the part of the
          foot between the metatarsus and the leg, consisting in
          man of seven short bones.
      (b) A plate of dense connective tissue or cartilage in the
          eyelid of man and many animals; -- called also tarsal
          cartilage, and tarsal plate.
          [1913 Webster]

   2. (Zool.) The foot of an insect or a crustacean. It usually
      consists of form two to five joints.
      [1913 Webster]

WordNet (r) 3.0 (2006):

tarsus
    n 1: the part of the foot of a vertebrate between the metatarsus
         and the leg; in human beings the bones of the ankle and
         heel collectively