refutal vs refutation

refutal and refutation both are nouns.

Word	Noun	Adjective	Verb	Adverb
refutal	Yes	No	No	No
refutation	Yes	No	No	No

As nouns, refutal and refutation are synonyms defined as:

Other synonyms of refutal include disproof, falsification, falsifying.

refutal (noun)	refutation (noun)
the act of determining that something is false	the act of determining that something is false
	any evidence that helps to establish the falsity of something
	the speech act of answering an attack on your assertions