American spelling vs optical fiber

American spelling and optical fiber both are nouns.

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

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