primary color vs American spelling

primary color and American spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
primary color	Yes	No	No	No
American spelling	Yes	No	No	No

primary color (noun)	American spelling (noun)
any of three colors from which all others can be obtained by mixing	English orthography used in the United States (characterized by 'analyze', 'center', 'usable')