nicotinic acid vs B complex

nicotinic acid and B complex both are nouns.

Word	Noun	Adjective	Verb	Adverb
nicotinic acid	Yes	No	No	No
B complex	Yes	No	No	No

As nouns, B complex is a hypernym of nicotinic acid; that is, B complex is a word with a broader meaning than nicotinic acid:

nicotinic acid: a B vitamin essential for the normal function of the nervous system and the gastrointestinal tract
B complex: originally thought to be a single vitamin but now separated into several B vitamins

Other hypernyms of nicotinic acid include B-complex vitamin, B, B vitamin, vitamin B, vitamin B complex.

nicotinic acid (noun)	B complex (noun)
a B vitamin essential for the normal function of the nervous system and the gastrointestinal tract	originally thought to be a single vitamin but now separated into several B vitamins