Dilaudid vs pain pill

Dilaudid and pain pill both are nouns.

Word	Noun	Adjective	Verb	Adverb
Dilaudid	Yes	No	No	No
pain pill	Yes	No	No	No

As nouns, pain pill is a hypernym of Dilaudid; that is, pain pill is a word with a broader meaning than Dilaudid:

Dilaudid: a narcotic analgesic (trade name Dilaudid) used to treat moderate to severe pain
pain pill: a medicine used to relieve pain

Other hypernyms of Dilaudid include analgesic, anodyne, painkiller.

Dilaudid (noun)	pain pill (noun)
a narcotic analgesic (trade name Dilaudid) used to treat moderate to severe pain	a medicine used to relieve pain