any of various arboreal anthropoid primates of the group or superfamily Platyrrhini, inhabiting forests from Mexico to Argentina and typically having a hairy face, widely separated nostrils, long arms, and a long, prehensile tail, and including the capuchin, douroucouli, howler monkey, marmoset, saki, spider monkey, squirrel monkey, titi, uakari, and woolly monkey.
any South American marmoset of the genera Saguinus and Leontopithecus (Leontideus), having silky fur and a nonprehensile tail: several species are threatened or endangered.
