colored vs negro

colored is a noun but negro is not a noun.

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

As adjectives, colored and negro are synonyms defined as:

Other synonyms of colored include coloured.

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

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