negro vs colored

negro is not a noun while colored is a noun.

Word	Noun	Adjective	Verb	Adverb
negro	No	Yes	No	No
colored	Yes	Yes	No	No

As adjectives, negro and colored are synonyms defined as:

Other synonyms of negro include coloured.

negro (noun)	colored (noun)
	a United States term for Blacks that is now considered offensive

negro (adjective)	colored (adjective)
having skin rich in melanin pigments;	having color or a certain color; sometimes used in combination
	(used of color) artificially produced; not natural
	having skin rich in melanin pigments;
	favoring one person or side over another