ace·​tyl ə-ˈsē-tᵊl How to pronounce acetyl (audio) ˈa-sə- How to pronounce acetyl (audio)
: the radical CH3CO− of acetic acid
often used in combination

Example Sentences

Recent Examples on the Web Goldford proposes that thioesters – and a molecule called pantetheine in particular – could play a similar role: when an acetyl group is stripped off, 33 kJ / mol of energy is generated. Jeffrey Marlow, Discover Magazine, 21 Mar. 2017 Prosecutors say police obtained detectable amounts of cocaine, heroin, fentanyl and acetyl fentanyl from both men. Cliff Pinckard, cleveland, 9 Mar. 2022 Add foods and high-quality supplements such as turmeric, omega-3s, vitamin B12, ginkgo biloba, phosphatidylserine, citicoline and acetyl-l-carnitine to enhance mental clarity and cognitive function. Serena Poon, Forbes, 24 Feb. 2021 The acetyl glycyl beta-alanine ingredient in the formula stood out to Jaliman, who says this peptide will probably help lighten the pigment of a scar while also working to even out skin tone. Maya Gandara,, 15 Apr. 2020 Buemi had a hunch that the same drug ring responsible for moving Molly into South Florida might also be importing the acetyl fentanyl pills. Alex W. Palmer, New York Times, 17 Oct. 2019 Her death was ruled an accidental overdose from fentanyl, acetyl fentanyl and cocaine. Eliza Fawcett,, 17 Oct. 2019 Several years ago, Oberdoerffer followed a hunch that cells might use another simple chemical unit, an acetyl group, on mRNA. Ken Garber, Science | AAAS, 1 July 2019 Cocaine, heroin and acetyl fentanyl were found in his system. Mark Curnutte,, 27 June 2018 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'acetyl.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


borrowed from German Acetyl, from Latin acētum "vinegar" + German -yl -yl — more at acetic acid

First Known Use

1864, in the meaning defined above

Time Traveler
The first known use of acetyl was in 1864

Dictionary Entries Near acetyl

Cite this Entry

“Acetyl.” Dictionary, Merriam-Webster, Accessed 30 May. 2023.

Medical Definition

: the radical CH3CO of acetic acid

More from Merriam-Webster on acetyl

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