fentanyl

noun

fen·​ta·​nyl ˈfen-tə-ˌnil How to pronounce fentanyl (audio)
nonstandard -ˌnȯl
: 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 is also responsible for shootings, killings, kidnappings and assaults and the distribution of at least 340 kilograms of fentanyl or fentanyl-laced narcotics, Blanche said. — ABC News, 27 Aug. 2026 An off-duty Wauconda firefighter is facing felony drug charges after she was found to have cocaine and fentanyl during a traffic stop. — Cbs Chicago Team, CBS News, 27 Aug. 2026 Bonta spoke Tuesday after a press conference about fentanyl and gun seizures at the attorney general’s office in downtown Los Angeles. — Gene Maddaus, Variety, 25 Aug. 2026 The department, which oversees agencies such ICE and Border Patrol, is also responsible for combating criminal organizations like cartels and for stopping drugs like fentanyl from entering the country through its agencies. — Miami Herald, 24 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 1 Sep. 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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