| Noun | 1. | Old World monkey - of Africa or Arabia or Asia; having nonprehensile tails and nostrils close togetherCercopithecidae, family Cercopithecidae - Old World monkeys: guenon; baboon; colobus monkey; langur; macaque; mandrill; mangabey; patas; proboscis monkey monkey - any of various long-tailed primates (excluding the prosimians) guenon, guenon monkey - small slender African monkey having long hind limbs and tail and long hair around the face mangabey - large agile arboreal monkey with long limbs and tail and white upper eyelids baboon - large terrestrial monkeys having doglike muzzles macaque - short-tailed monkey of rocky regions of Asia and Africa langur - slender long-tailed monkey of Asia colobus, colobus monkey - arboreal monkey of western and central Africa with long silky fur and reduced thumbs Nasalis larvatus, proboscis monkey - Borneo monkey having a long bulbous nose |