Word Origin & History
aurochs
1766, misapplication to the European bison (Bos Bison) of a word that actually refers to a species of wild ox (Bos Ursus) that went extinct 17c., from Ger. Aurochs, from O.H.G. urohso, from uro "aurochs" (cognate with O.E. ur, O.N. ürr), of unknown origin, + ohso "ox." L. urus and Gk. ouros are P.Gmc. loan-words.