WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
noun.
trade names of a narcotic analgesic that can be inhaled and that acts on the central nervous system and may become addictive; used as a veterinary anesthetic and with other drugs before, during, and after surgery; also used as a nonlethal gas to incapacitate people in hostage situations; also abused as a recreational drug
Word Usage
"Onsolis is an opioid called fentanyl, which is often given as a patch to help manage severe pain."