pronghorn Antilocapra americana, an animal which has some characteristics in common with the antelope but differs in belonging to the New World (whereas all true antelopes are of the Old World) and in having hollow branching horns, such as no other animal possesses; so it is classified in a family of its own, Antilocapridae. It, and its family with it, almost became extinct at the beginning of the 20th century, when numbers had dwindled from 75 million to a mere 20,000; but it was saved and restricted hunting for it is now allowed in some states.