elk vs wapiti

elk and wapiti both are nouns.

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

As nouns, elk and wapiti are synonyms defined as:

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

As nouns, elk and wapiti are synonyms defined as:

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

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

elk (noun)	wapiti (noun)
large northern deer with enormous flattened antlers in the male; called `elk' in Europe and `moose' in North America	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
large North American deer with large much-branched antlers in the male