endorsement vs okey

endorsement and okey both are nouns.

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

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

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

endorsement (noun)	okey (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