kaffir vs Black African

kaffir and Black African both are nouns.

Word	Noun	Adjective	Verb	Adverb
kaffir	Yes	No	No	No
Black African	Yes	No	No	No

As nouns, Black African is a hypernym of kaffir; that is, Black African is a word with a broader meaning than kaffir:

kaffir (noun)	Black African (noun)
an offensive and insulting term for any Black African	an African who is Black
important for human and animal food; growth habit and stem form similar to Indian corn but having sawtooth-edged leaves