gram molecule vs weight unit

gram molecule and weight unit both are nouns.

Word	Noun	Adjective	Verb	Adverb
gram molecule	Yes	No	No	No
weight unit	Yes	No	No	No

As nouns, weight unit is a hypernym of gram molecule; that is, weight unit is a word with a broader meaning than gram molecule:

gram molecule: the molecular weight of a substance expressed in grams; the basic unit of amount of substance adopted under the Systeme International d'Unites
weight unit: a decimal unit of weight based on the gram

Other hypernyms of gram molecule include metric weight unit.

gram molecule (noun)	weight unit (noun)
the molecular weight of a substance expressed in grams; the basic unit of amount of substance adopted under the Systeme International d'Unites	a unit used to measure weight
	a decimal unit of weight based on the gram