antitumor vs American spelling

antitumor is not a noun while American spelling is a noun.

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

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

antitumor (adjective)	American spelling (adjective)
used in the treatment of cancer