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A genus (now called Macaca) of Old World monkeys of the family Cercopithecidae, originally comprising a large number of African and Asian species, but later restricted to a smaller number of chiefly Asian species; (also macacus) a member of this genus, a macaque.
Although it was the name used throughout the 19th century, Macacus is now considered an invalid variant of Macaca in zoological nomenclature.
Mid 19th century; earliest use found in Henry McMurtrie (1793–1865). From scientific Latin Macacus, alteration of Macaca from French macaque.