myelinization vs American spelling

myelinization and American spelling both are nouns.

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

myelinization (noun)	American spelling (noun)
the development of a myelin sheath around a nerve fiber	English orthography used in the United States (characterized by 'analyze', 'center', 'usable')