affiliate vs companion

affiliate and companion both are nouns.

Word	Noun	Adjective	Verb	Adverb
affiliate	Yes	No	Yes	No
companion	Yes	No	Yes	No

As verbs, companion is a hyponym of affiliate; that is, companion is a word with a more specific, narrower meaning than affiliate:

Other hyponyms of affiliate include ally, date, go out, go steady, see, accompany, company, keep company.

affiliate (noun)	companion (noun)
a subsidiary or subordinate organization that is affiliated with another organization	a friend who is frequently in the company of another
a subordinate or subsidiary associate; a person who is affiliated with another or with an organization	one paid to accompany or assist or live with another
	a traveler who accompanies you

affiliate (verb)	companion (verb)
join in an affiliation	be a companion to somebody
keep company with; hang out with