recuse vs recusation

recuse is not a noun while recusation is a noun.

Word	Noun	Adjective	Verb	Adverb
recuse	No	No	Yes	No
recusation	Yes	No	No	No

recuse (noun)	recusation (noun)
	(law) the disqualification of a judge or jury by reason of prejudice or conflict of interest; a judge can be recused by objections of either party or judges can disqualify themselves
	(law) an objection grounded on the judge's relationship to one of the parties

recuse (verb)	recusation (verb)
challenge or except to a judge as being incompetent or interested, in canon and civil law
disqualify oneself (as a judge) in a particular case