American spelling vs itemize

American spelling is a noun but itemize is not a noun.

Word	Noun	Adjective	Verb	Adverb
American spelling	Yes	No	No	No
itemize	No	No	Yes	No

American spelling (noun)	itemize (noun)
English orthography used in the United States (characterized by 'analyze', 'center', 'usable')

American spelling (verb)	itemize (verb)
	specify individually
	place on a list of items