papillary tumor vs American spelling

papillary tumor and American spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
papillary tumor	Yes	No	No	No
American spelling	Yes	No	No	No

papillary tumor (noun)	American spelling (noun)
a benign epithelial tumor forming a rounded mass	English orthography used in the United States (characterized by 'analyze', 'center', 'usable')