polymerization vs American spelling

polymerization and American spelling both are nouns.

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

polymerization (noun)	American spelling (noun)
a chemical process that combines several monomers to form a polymer or polymeric compound	English orthography used in the United States (characterized by 'analyze', 'center', 'usable')