The Collaborative International Dictionary
Macacus silenus
Wanderoo \Wan`der*oo"\, n. [Cingalese wanderu a monkey.] (Zo["o]l.) A large monkey ( Macacus silenus) native of Malabar. It is black, or nearly so, but has a long white or gray beard encircling the face. Called also maha, silenus, neelbhunder, lion-tailed baboon, and great wanderoo.
Note: The name is sometimes applied also to other allied species.