Source : Webster's Revised Unabridged Dictionary (1913)

Hartbeest \Hart"beest`\, n. [D. hertebeest. See {Hart}, and
   {Beast}.] (Zo["o]l.)
   A large South African antelope ({Alcelaphus caama}), formerly
   much more abundant than it is now. The face and legs are
   marked with black, the rump with white. [Written also
   {hartebeest}, and {hartebest}.]

Source : WordNet®

hartebeest
     n : a large African antelope with lyre-shaped horns that curve
         backward