The Collaborative International Dictionary of English v.0.48:

Grivet \Griv"et\ (gr[i^]v"[e^]t), n. [Cf. F. grivet.] (Zool.)
   A monkey of the upper Nile and Abyssinia (Cercopithecus
   griseo-viridis), having the upper parts dull green, the
   lower parts white, the hands, ears, and face black. It was
   known to the ancient Egyptians. Called also tota.
   [1913 Webster]

WordNet (r) 3.0 (2006):

grivet
    n 1: white and olive green East African monkey with long white
         tufts of hair beside the face [syn: grivet,
         Cercopithecus aethiops]