debater vs disprover

debater and disprover both are nouns.

Word	Noun	Adjective	Verb	Adverb
debater	Yes	No	No	No
disprover	Yes	No	No	No

As nouns, disprover is a hyponym of debater; that is, disprover is a word with a more specific, narrower meaning than debater:

debater: someone who engages in debate
disprover: a debater who refutes or disproves by offering contrary evidence or argument

Other hyponyms of debater include devil's advocate, confuter, rebutter, refuter, wrangler.

debater (noun)	disprover (noun)
someone who engages in debate	a debater who refutes or disproves by offering contrary evidence or argument