American spelling vs sensitizing

American spelling and sensitizing both are nouns.

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

American spelling (noun)	sensitizing (noun)
English orthography used in the United States (characterized by 'analyze', 'center', 'usable')	rendering an organism sensitive to a serum by a series of injections

American spelling (adjective)	sensitizing (adjective)
	making susceptible or sensitive to either physical or emotional stimuli