self-fertilization vs American spelling

self-fertilization and American spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
self-fertilization	Yes	No	No	No
American spelling	Yes	No	No	No

self-fertilization (noun)	American spelling (noun)
fertilization by the union of male and female gametes from the same individual	English orthography used in the United States (characterized by 'analyze', 'center', 'usable')