noun

• 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.