phenacetin vs pain pill

phenacetin and pain pill both are nouns.

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

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

phenacetin: a white crystalline compound used as an analgesic and also as an antipyretic
pain pill: a medicine used to relieve pain

Other hypernyms of phenacetin include analgesic, anodyne, painkiller.

phenacetin (noun)	pain pill (noun)
a white crystalline compound used as an analgesic and also as an antipyretic	a medicine used to relieve pain