attest vs attestation

attest is not a noun while attestation is a noun.

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

attest (noun)	attestation (noun)
	the action of bearing witness
	the evidence by which something is attested

attest (verb)	attestation (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