Taxonomy defines several classes which a species falls into. These are: Kingdom, Phylum, Class, Order, Family, Genus, and finally Species. As you specify only "Monkey", what species name is...
Gorillas, apes, primates, chimpanzees, orangutans, baboons, marmosets, tamarins, bush babies, spider monkeys, howler monkeys, sakis, and capuchins are all part of the monkey 'family'.