Webster's Revised Unabridged Dictionary · 1913

Mangabey

Mangabey , noun

[So called by Buffon from Mangaby, in Madagascar, where he erroneously supposed them be native.]

(Zoology) Any one of several African monkeys of the genus Cercocebus, as the sooty mangabey (Cercocebus fuliginosus), which is sooty black.