American elk vs Cervus

American elk and Cervus both are nouns.

Word	Noun	Adjective	Verb	Adverb
American elk	Yes	No	No	No
Cervus	Yes	No	No	No

American elk (noun)	Cervus (noun)
large North American deer with large much-branched antlers in the male	the type genus of the Cervidae
common deer of temperate Europe and Asia