encyclopedia vs American spelling

encyclopedia and American spelling both are nouns.

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

encyclopedia (noun)	American spelling (noun)
a reference work (often in several volumes) containing articles on various topics (often arranged in alphabetical order) dealing with the entire range of human knowledge or with some particular specialty	English orthography used in the United States (characterized by 'analyze', 'center', 'usable')