pain pill vs medicament

pain pill and medicament both are nouns.

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

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

pain pill: a medicine used to relieve pain
medicament: (medicine) something that treats or prevents or alleviates the symptoms of disease

Other hypernyms of pain pill include medication, medicinal drug, medicine.

pain pill (noun)	medicament (noun)
a medicine used to relieve pain	(medicine) something that treats or prevents or alleviates the symptoms of disease