endorsement vs okay

endorsement and okay both are nouns.

Word	Noun	Adjective	Verb	Adverb
endorsement	Yes	No	No	No
okay	Yes	Yes	Yes	Yes

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

Other hyponyms of endorsement include O.K., OK, okeh, okey, visa, nihil obstat.

endorsement (noun)	okay (noun)
the act of endorsing	an endorsement
formal and explicit approval
a promotional statement (as found on the dust jackets of books)
a speech seconding a motion
a signature that validates something

endorsement (adjective)	okay (adjective)
	being satisfactory or in satisfactory condition

endorsement (verb)	okay (verb)
	give sanction to

endorsement (adverb)	okay (adverb)
	in a satisfactory or adequate manner