Assertion: opium's morphine | /r/HasProperty | an opioid pain reliever
Facets:
Source sentences:
text: Opium tincture contains morphine which is an opioid pain reliever.
text: Opiates in general, and morphine in particular are narcotic pain relievers.
text: Morphine is an opioid pain reliever and changes the way the brain perceives pain.