antiemetic vs Phenergan

antiemetic and Phenergan both are nouns.

Word	Noun	Adjective	Verb	Adverb
antiemetic	Yes	No	No	No
Phenergan	Yes	No	No	No

As nouns, Phenergan is a hyponym of antiemetic; that is, Phenergan is a word with a more specific, narrower meaning than antiemetic:

antiemetic: a drug that prevents or alleviates nausea and vomiting
Phenergan: antihistamine (trade name Phenergan) used to treat allergies; also an antiemetic used to treat motion sickness

Other hyponyms of antiemetic include dimenhydrinate, Dramamine, Emetrol, prochlorperazine, promethazine.

antiemetic (noun)	Phenergan (noun)
a drug that prevents or alleviates nausea and vomiting	antihistamine (trade name Phenergan) used to treat allergies; also an antiemetic used to treat motion sickness