The word rhinoceros is derived through Latin from the Ancient Greek: ῥῑνόκερως, which is composed of ῥῑνο- (rhino- ,  nose ) and κέρας (keras,  horn ). The plural in English is rhinoceros or rhinoceroses. The collective noun for a group of rhinoceroses is crash or herd.hinoceros are killed by humans for their horns, which are bought and sold on the black market, and which are used by some cultures for ornamental or traditional medicinal purposes. East Asia, specifically Vietnam, is the largest market for rhino horns.