hippopotamus
nounNAmE//ˌhɪpəˈpɑt̮əməs//
(pl. hippopotamuses NAmE//ˌhɪpəˈpɑt̮əməsəz//
or hippopotami NAmE//ˌhɪpəˈpɑt̮əmaɪ//
) (informal hippo)Check pronunciation: hippopotamus
Definition of hippopotamus noun from the Oxford Advanced American Dictionary