poetry vs epos

poetry and epos both are nouns.

Word	Noun	Adjective	Verb	Adverb
poetry	Yes	No	No	No
epos	Yes	No	No	No

As nouns, epos is a hyponym of poetry; that is, epos is a word with a more specific, narrower meaning than poetry:

poetry: literature in metrical form
epos: a body of poetry that conveys the traditions of a society by treating some epic theme

Other hyponyms of poetry include epic poetry, heroic poetry.

poetry (noun)	epos (noun)
literature in metrical form	a long narrative poem telling of a hero's deeds
any communication resembling poetry in beauty or the evocation of feeling	a body of poetry that conveys the traditions of a society by treating some epic theme