fentanyl

noun

fen·​ta·​nyl ˈfen-tə-ˌnil How to pronounce fentanyl (audio)
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The group distributed them — along with test strips that identify other harmful adulterants, such as fentanyl, xylazine, and medetomidine — at clinics and neighborhood events. — Scott Maucione, NPR, 8 Aug. 2026 Mexican authorities have dismantled well over a thousand clandestine drug laboratories, seized enormous quantities of narcotics and fentanyl pills, arrested thousands of cartel operatives, and extradited major criminal figures to the United States. — Chris Shays, Hartford Courant, 7 Aug. 2026 An autopsy later showed there was no fentanyl in Williams’ system. — Julia Coin august 7, Charlotte Observer, 7 Aug. 2026 Authorities said fentanyl can be sold as pills, with some online dealers claiming the pills are Xanax, Percocet or oxycodone. — Rosalio Ahumada, Sacbee.com, 6 Aug. 2026 See All Example Sentences for fentanyl

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

Time Traveler
The first known use of fentanyl was in 1964

Rhymes for fentanyl

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Browse Nearby Words

fent
fentanyl
fenthion
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Cite this Entry

“Fentanyl.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fentanyl. Accessed 15 Aug. 2026.

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Medical Definition

fentanyl

noun
fen·​ta·​nyl ˈfent-ᵊn-ˌil How to pronounce fentanyl (audio)
: 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.

More from Merriam-Webster on fentanyl

Britannica.com: Encyclopedia article about fentanyl

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