attester vs attest

attester is a noun but attest is not a noun.

Word	Noun	Adjective	Verb	Adverb
attester	Yes	No	No	No
attest	No	No	Yes	No

attester (noun)	attest (noun)
someone who affirms or vouches for the correctness or truth or genuineness of something

attester (verb)	attest (verb)
	authenticate, affirm to be true, genuine, or correct, as in an official capacity
	provide evidence for; stand as proof of; show by one's behavior, attitude, or external attributes
	give testimony in a court of law
	establish or verify the usage of