black magic vs magic

black magic and magic both are nouns.

Word	Noun	Adjective	Verb	Adverb
black magic	Yes	No	No	No
magic	Yes	Yes	No	No

As nouns, magic is a hypernym of black magic; that is, magic is a word with a broader meaning than black magic:

black magic: the belief in magical spells that harness occult forces or evil spirits to produce unnatural effects in the world
magic: any art that invokes supernatural powers

Other hypernyms of black magic include thaumaturgy.

black magic (noun)	magic (noun)
the belief in magical spells that harness occult forces or evil spirits to produce unnatural effects in the world	an illusory feat; considered magical by naive observers
	any art that invokes supernatural powers

black magic (adjective)	magic (adjective)
	possessing or using or characteristic of or appropriate to supernatural powers