acetyl

noun

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

Examples of acetyl 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 complex also contains a blend of antioxidants, flax seed extract, and acetyl tetrapeptide-2, which work together to improve skin elasticity, maximize hydration, and even out the skin tone across the neck and décolleté. — Christa Joanna Lee, Glamour, 23 Oct. 2026 This concealer contains acetyl hexapeptide-8, a peptide commonly associated with targeting the appearance of expression lines. — Mickey Williams, Flow Space, 9 Oct. 2026 Preceded by the Best of Beauty-winning P-Tiox Serum, this moisturizer uses the same tripeptide (acetyl hexapeptide-8), which may help reduce the appearance of expression lines by limiting the muscle contractions that contribute to them. — Sheryl George, Allure, 5 Oct. 2026 Okoaskin is one of the brands putting IDEALIFT™ (acetyl dipeptide-1 cetyl ester) to work in its lifting cream. — Matthew Kayser, USA Today, 10 Sep. 2026 See All Example Sentences for acetyl

Word History

Etymology

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

Phrases Containing acetyl

Rhymes for acetyl

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Browse Nearby Words

aceturic acid
acetyl
acetylacetonate
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Cite this Entry

“Acetyl.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acetyl. Accessed 27 Oct. 2026.

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