extemporize vs American spelling

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

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

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

extemporize (verb)	American spelling (verb)
perform without preparation
manage in a makeshift way; do with whatever is at hand