sleeping capsule vs soporific

sleeping capsule and soporific both are nouns.

Word	Noun	Adjective	Verb	Adverb
sleeping capsule	Yes	No	No	No
soporific	Yes	Yes	No	No

As nouns, soporific is a hypernym of sleeping capsule; that is, soporific is a word with a broader meaning than sleeping capsule:

sleeping capsule: a soporific drug in the form of a pill (or tablet or capsule)
soporific: a drug that induces sleep

Other hypernyms of sleeping capsule include lozenge, pill, tab, tablet, hypnotic.

sleeping capsule (noun)	soporific (noun)
a soporific drug in the form of a pill (or tablet or capsule)	a drug that induces sleep

sleeping capsule (adjective)	soporific (adjective)
	sleep inducing
	inducing mental lethargy