propoxyphene vs painkiller

propoxyphene and painkiller both are nouns.

Word	Noun	Adjective	Verb	Adverb
propoxyphene	Yes	No	No	No
painkiller	Yes	No	No	No

As nouns, painkiller is a hypernym of propoxyphene; that is, painkiller is a word with a broader meaning than propoxyphene:

propoxyphene: a mildly narcotic analgesic drug (trade name Darvon) related to methadone but less addictive
painkiller: a medicine used to relieve pain

Other hypernyms of propoxyphene include analgesic, anodyne, pain pill.

propoxyphene (noun)	painkiller (noun)
a mildly narcotic analgesic drug (trade name Darvon) related to methadone but less addictive	a medicine used to relieve pain