vitamin vs nourishment

vitamin and nourishment both are nouns.

Word	Noun	Adjective	Verb	Adverb
vitamin	Yes	No	No	No
nourishment	Yes	No	No	No

As nouns, nourishment is a hypernym of vitamin; that is, nourishment is a word with a broader meaning than vitamin:

vitamin: any of a group of organic substances essential in small quantities to normal metabolism
nourishment: a source of materials to nourish the body

Other hypernyms of vitamin include aliment, alimentation, nutriment, nutrition, sustenance, victuals.

vitamin (noun)	nourishment (noun)
any of a group of organic substances essential in small quantities to normal metabolism	the act of nourishing
	a source of materials to nourish the body