a large, fierce, strong baboon (Mandrillus sphinx) of W Africa: the male has blue and scarlet patches on the face and rump
Origin:
man + drill
See mandrill in American Heritage Dictionary 4
noun
A large fierce baboon (Papio sphinx syn. Mandrillus sphinx) of western Africa, having a beard, crest, and mane and brilliant blue, purple, and scarlet facial markings in the adult male.