The Collaborative International Dictionary of English v.0.48:

Anoa \A*noa"\, n. [Native name.] (Zool.)
   A small wild ox of Celebes (Anoa depressicornis), allied to
   the buffalo, but having long nearly straight horns.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Anoa depressicornis
    n 1: small buffalo of the Celebes having small straight horns
         [syn: anoa, dwarf buffalo, Anoa depressicornis]