Negro vs worker

Negro and worker both are nouns.

Word	Noun	Adjective	Verb	Adverb
Negro	Yes	No	No	No
worker	Yes	No	No	No

As nouns, worker is a hypernym of Negro; that is, worker is a word with a broader meaning than Negro:

Negro: a person with African ancestry, "Negro" and "Negroid" are archaic and pejorative today
worker: a person who acts and gets things done

Other hypernyms of Negro include actor, doer.

Negro (noun)	worker (noun)
a person with African ancestry, "Negro" and "Negroid" are archaic and pejorative today	sterile member of a colony of social insects that forages for food and cares for the larvae
	a person who works at a specific occupation
	a member of the working class (not necessarily employed)
	a person who acts and gets things done