Definition of oxycodone hydrochloride

oxycodone hydrochloride (OK-see-KOH-done HY-droh-KLOR-ide): A drug used to relieve moderate to severe pain. Oxycodone hydrochloride is made in a lab by modifying thebaine, a natural substance found in the opium poppy plant. It works by binding to mu opioid receptors in the central nervous system, which blocks pain signals and changes how the body responds to pain. Oxycodone hydrochloride is a type of semi-synthetic opioid agonist that works as an analgesic (pain reliever).