optical fiber vs American spelling

optical fiber and American spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
optical fiber	Yes	No	No	No
American spelling	Yes	No	No	No

optical fiber (noun)	American spelling (noun)
a very thin fiber made of glass that functions as a waveguide for light; used in bundles to transmit images	English orthography used in the United States (characterized by 'analyze', 'center', 'usable')