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

Toxicology confirmed the presence of both fentanyl and cocaine in the infant’s heart blood and liver blood. —Rick Sobey, Boston Herald, 24 Nov. 2025

According to the Westmoreland County District Attorney's Office, on October 4, Monessen Police and Westmoreland County Detectives learned that a 2-year-old child was being treated at UPMC Children's Hospital after testing positive for cocaine and fentanyl. —Patrick Damp, CBS News, 21 Nov. 2025

These panels can reliably identify heroin, oxycodone, and fentanyl, but fail to catch nitazenes, brorphine, or other new synthetic analogs. —Dr. Shravani Durbhakula, Time, 19 Nov. 2025

The announcement prompted nefarious actors to begin shipping the precursor chemicals to other countries, where it is then made into fentanyl. —Mike Brest, The Washington Examiner, 16 Nov. 2025

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.