American elk vs wapiti

American elk and wapiti both are nouns.

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

As nouns, American elk and wapiti are synonyms defined as:

American elk and wapiti: large North American deer with large much-branched antlers in the male

Other synonyms of American elk include Cervus elaphus canadensis, elk.

As nouns, American elk and wapiti are synonyms defined as:

Other synonyms of American elk include Cervus elaphus, elk, red deer.

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