aurochs vs bison

aurochs and bison both are nouns.

Word	Noun	Adjective	Verb	Adverb
aurochs	Yes	No	No	No
bison	Yes	No	No	No

As nouns, bison is a hypernym of aurochs; that is, bison is a word with a broader meaning than aurochs:

aurochs: European bison having a smaller and higher head than the North American bison
bison: any of several large humped bovids having shaggy manes and large heads and short horns

aurochs (noun)	bison (noun)
large recently extinct long-horned European wild ox; considered one of the ancestors of domestic cattle	any of several large humped bovids having shaggy manes and large heads and short horns
European bison having a smaller and higher head than the North American bison