sleeping capsule vs hypnotic

sleeping capsule and hypnotic both are nouns.

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

As nouns, hypnotic is a hypernym of sleeping capsule; that is, hypnotic 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)
hypnotic: a drug that induces sleep

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

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

sleeping capsule (adjective)	hypnotic (adjective)
	of or relating to hypnosis
	attracting and holding interest as if by a spell