attestator vs attestor

attestator and attestor both are nouns.

Word	Noun	Adjective	Verb	Adverb
attestator	Yes	No	No	No
attestor	Yes	No	No	No

As nouns, attestator and attestor are synonyms defined as:

attestator and attestor: (law) a person who attests to the genuineness of a document or signature by adding their own signature

Other synonyms of attestator include attestant, witness.

attestator (noun)	attestor (noun)
(law) a person who attests to the genuineness of a document or signature by adding their own signature	(law) a person who attests to the genuineness of a document or signature by adding their own signature