mephobarbital vs anticonvulsant

mephobarbital and anticonvulsant both are nouns.

Word	Noun	Adjective	Verb	Adverb
mephobarbital	Yes	No	No	No
anticonvulsant	Yes	No	No	No

As nouns, anticonvulsant is a hypernym of mephobarbital; that is, anticonvulsant is a word with a broader meaning than mephobarbital:

mephobarbital: a long-acting crystalline barbiturate (trade name Mebaral) used as a sedative and as an anticonvulsant in the treatment of epilepsy
anticonvulsant: a drug used to treat or prevent convulsions (as in epilepsy)

Other hypernyms of mephobarbital include anticonvulsant drug, antiepileptic, antiepileptic drug, barbiturate.

mephobarbital (noun)	anticonvulsant (noun)
a long-acting crystalline barbiturate (trade name Mebaral) used as a sedative and as an anticonvulsant in the treatment of epilepsy	a drug used to treat or prevent convulsions (as in epilepsy)