neutral vs bluish black

neutral is a noun but bluish black is not a noun.

Word	Noun	Adjective	Verb	Adverb
neutral	Yes	Yes	No	No
bluish black	No	Yes	No	No

neutral (noun)	bluish black (noun)
one who does not side with any party in a war or dispute

neutral (adjective)	bluish black (adjective)
having no hue	of black tinged with blue
possessing no distinctive quality or characteristics
lacking distinguishing quality or characteristics
not supporting or favoring either side in a war, dispute, or contest
having no personal preference
having no net electric charge
having only a limited ability to react chemically; chemically inactive