incursion vs incur

incursion is a noun but incur is not a noun.

Word	Noun	Adjective	Verb	Adverb
incursion	Yes	No	No	No
incur	No	No	Yes	No

incursion (noun)	incur (noun)
an attack that penetrates into enemy territory
the act of entering some territory or domain (often in large numbers)
the mistake of incurring liability or blame

incursion (verb)	incur (verb)
	receive a specified treatment (abstract)
	make oneself subject to; bring upon oneself; become liable to