nil vs relative quantity

nil and relative quantity both are nouns.

Word	Noun	Adjective	Verb	Adverb
nil	Yes	No	No	No
relative quantity	Yes	No	No	No

As nouns, relative quantity is a hypernym of nil; that is, relative quantity is a word with a broader meaning than nil:

nil: a quantity of no importance; thing (object:), singular, negative pronoun; pronoun, thing, singular; quantifier: negative existential
relative quantity: a quantity relative to some purpose

nil (noun)	relative quantity (noun)
a quantity of no importance; thing (object:), singular, negative pronoun; pronoun, thing, singular; quantifier: negative existential	a quantity relative to some purpose