certificate vs certify

certificate is a noun but certify is not a noun.

Word	Noun	Adjective	Verb	Adverb
certificate	Yes	No	Yes	No
certify	No	No	Yes	No

certificate (noun)	certify (noun)
a document attesting to the truth of certain stated facts
a formal declaration that documents a fact of relevance to finance and investment; the holder has a right to receive interest or dividends

certificate (verb)	certify (verb)
authorize by certificate	provide evidence for; stand as proof of; show by one's behavior, attitude, or external attributes
present someone with a certificate	declare legally insane
	guarantee payment on; of checks
	guarantee as meeting a certain standard
	authorize officially