attestant vs witnesser

attestant and witnesser both are nouns.

Word	Noun	Adjective	Verb	Adverb
attestant	Yes	No	No	No
witnesser	Yes	No	No	No

As nouns, witnesser is a hypernym of attestant; that is, witnesser is a word with a broader meaning than attestant:

attestant: someone who affirms or vouches for the correctness or truth or genuineness of something
witnesser: someone who sees an event and reports what happened

Other hypernyms of attestant include informant, witness.

attestant (noun)	witnesser (noun)
(law) a person who attests to the genuineness of a document or signature by adding their own signature	someone who sees an event and reports what happened
someone who affirms or vouches for the correctness or truth or genuineness of something