tab vs sleeping draught

tab and sleeping draught both are nouns.

Word	Noun	Adjective	Verb	Adverb
tab	Yes	No	No	No
sleeping draught	Yes	No	No	No

As nouns, sleeping draught is a hyponym of tab; that is, sleeping draught is a word with a more specific, narrower meaning than tab:

tab: a dose of medicine in the form of a small pellet
sleeping draught: a soporific drug in the form of a pill (or tablet or capsule)

Other hyponyms of tab include bolus, capsule, dragee, sleeping capsule, sleeping pill, sleeping tablet.

tab (noun)	sleeping draught (noun)
a dose of medicine in the form of a small pellet	a soporific drug in the form of a pill (or tablet or capsule)
a short strip of material attached to or projecting from something in order to facilitate opening or identifying or handling it
the key on a typewriter or a word processor that causes a tabulation
the bill in a restaurant
sensationalist journalism