| Noun | 1. | Fentanyl - 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 drugopiate - a narcotic drug that contains opium or an opium derivative | |