The Collaborative International Dictionary of English v.0.48:

Gaur \Gaur\ (g[add]r or gour), n. [Native name.] (Zool.)
   An East Indian species of wild cattle (Bibos gauris), of
   large size and an untamable disposition. [Spelt also gour.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

gaur
    n 1: wild ox of mountainous areas of eastern India [syn: gaur,
         Bibos gaurus]