acetaldehyde

noun

ac·​et·​al·​de·​hyde ˌa-sə-ˈtal-də-ˌhīd How to pronounce acetaldehyde (audio)
: a colorless volatile water-soluble liquid aldehyde C2H4O used chiefly in organic synthesis

Examples of acetaldehyde in a Sentence

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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.
This process results in toxic compounds, such as acetaldehyde, that can cause liver inflammation. — Angela Ryan Lee, Verywell Health, 10 Mar. 2026 That answer came in the form of a class of enzymes in the dehydrogenase family, which are some of the catalysts that convert acetaldehyde to ethanol. — Christopher Null, Wired News, 11 Nov. 2025 The frozen COMs that were confirmed to exist around ST6 include acetaldehyde, acetic acid, ethanol, methanol and methyl formate. — Keith Cooper, Space.com, 7 Nov. 2025 The heat of a home dryer can vaporize some compounds, producing small amounts of acetaldehyde and benzene, compounds also deemed to be carcinogens, increasing the risk of blood cancers. — Angelique Brenes, PEOPLE, 16 June 2026 See All Example Sentences for acetaldehyde

Word History

Etymology

borrowed from German Acetaldehyd, from acet- acet- + Aldehyd aldehyde

First Known Use

1857, in the meaning defined above

Time Traveler
The first known use of acetaldehyde was in 1857

Rhymes for acetaldehyde

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Browse Nearby Words

acetaldehydase
acetaldehyde
acetaldehyde ammonia
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Cite this Entry

“Acetaldehyde.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acetaldehyde. Accessed 7 Jul. 2026.

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Medical Definition

acetaldehyde

noun
ac·​et·​al·​de·​hyde ˌas-ə-ˈtal-də-ˌhīd How to pronounce acetaldehyde (audio)
: a colorless volatile water-soluble liquid aldehyde C2H4O used chiefly in organic synthesis that can cause irritation to mucous membranes

More from Merriam-Webster on acetaldehyde

Nglish: Translation of acetaldehyde for Spanish Speakers

Britannica.com: Encyclopedia article about acetaldehyde

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