American spelling vs city center

American spelling and city center both are nouns.

Word	Noun	Adjective	Verb	Adverb
American spelling	Yes	No	No	No
city center	Yes	No	No	No

American spelling (noun)	city center (noun)
English orthography used in the United States (characterized by 'analyze', 'center', 'usable')	the central part of a city