persevere vs perseveration

persevere is not a noun while perseveration is a noun.

Word	Noun	Adjective	Verb	Adverb
persevere	No	No	Yes	No
perseveration	Yes	No	No	No

persevere (noun)	perseveration (noun)
	the act of persisting or persevering; continuing or repeating behavior
	the tendency for a memory or idea to persist or recur without any apparent stimulus for it

persevere (verb)	perseveration (verb)
be persistent, refuse to stop