fentanyl

noun

fen·​ta·​nyl ˈfen-tə-ˌnil 

: a synthetic opioid narcotic analgesic C₂₂H₂₈N₂O with pharmacological action similar to morphine that is administered transdermally as a skin patch and in the form of its citrate C₂₂H₂₈N₂O·C₆H₈O₇ is administered orally or parenterally (as by intravenous or epidural injection)

Examples of fentanyl in a Sentence

Recent Examples on the Web

Jackson Browne's son, Ethan, died from the effects of fentanyl, methamphetamine, and lidocaine. —Wesley Stenzel, Entertainment Weekly, 14 Jan. 2026

Cole Kryger’s death was caused by combined fentanyl and methamphetamine toxicity in an accident, according to the Tarrant County Medical Examiner’s Office. —Emerson Clarridge, Fort Worth Star-Telegram, 13 Jan. 2026

This was the first such decline in 33 years and one that was sustained month after month, most dramatically for deaths caused by illicit fentanyl. —Charles Lebaron, Time, 13 Jan. 2026

Venezuela may not be the sole source of cocaine, nor a major conduit for fentanyl, but dismantling a regime that actively protects and profits from transnational criminal networks unquestionably degrades those networks’ capacity to operate. —Timothy M. Herbst, Hartford Courant, 13 Jan. 2026

Word History

Etymology

probably alteration of phenethyl, a monovalent radical derived from ethylbenzine, from phen- + ethyl

First Known Use

1964, in the meaning defined above

Medical Definition

fentanyl

noun

fen·​ta·​nyl ˈfent-ᵊn-ˌil 

: a synthetic opioid narcotic analgesic C₂₂H₂₈N₂O with pharmacological action similar to morphine that is administered transdermally as a skin patch and in the form of its citrate C₂₂H₂₈N₂O·C₆H₈O₇ is administered orally or parenterally

Note: Fentanyl is marketed under the trademark Actiq.