subtilize vs American spelling

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

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

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

subtilize (verb)	American spelling (verb)
make more subtle or refined
make (senses) more keen
mark fine distinctions and subtleties, as among words