of a superorder (Marsupialia) of mammals that lack a placenta and have an external abdominal pouch (marsupium) containing the teats: the incompletely developed offspring nurses within this pouch for several months after birth to complete its development
an animal of this kind, as a kangaroo, opossum, or wombat
Any of various mammals of the order Marsupialia, whose young are very undeveloped when born and continue developing outside their mother's body attached to one of her nipples. Most marsupials have longer hindlegs than forelimbs, and the females usually have pouches in which they carry their young. Kangaroos, opossums, and koalas are marsupials.