nigga vs blackamoor

nigga and blackamoor both are nouns.

Word	Noun	Adjective	Verb	Adverb
nigga	Yes	No	No	No
blackamoor	Yes	No	No	No

As nouns, blackamoor is a hypernym of nigga; that is, blackamoor is a word with a broader meaning than nigga:

nigga: (ethnic slur) extremely offensive name for a Black person
blackamoor: a person with dark skin who comes from Africa (or whose ancestors came from Africa)

Other hypernyms of nigga include African-American, Black, Negro, Negroid, Black person.

nigga (noun)	blackamoor (noun)
(ethnic slur) extremely offensive name for a Black person	a person with dark skin who comes from Africa (or whose ancestors came from Africa)