American spelling vs diagonalization

American spelling and diagonalization both are nouns.

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

American spelling (noun)	diagonalization (noun)
English orthography used in the United States (characterized by 'analyze', 'center', 'usable')	changing a square matrix to diagonal form (with all non-zero elements on the principal diagonal)