acetaldehyde

noun

ac·​et·​al·​de·​hyde ˌa-sə-ˈtal-də-ˌhīd 

: a colorless volatile water-soluble liquid aldehyde C₂H₄O used chiefly in organic synthesis

Examples of acetaldehyde in a Sentence

Recent Examples on the Web

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

Some chemicals produced by e-cigarettes include formaldehyde and acetaldehyde, which are known to cause both lung and heart disease. —Omer Awan, Forbes.com, 1 Sep. 2025

The idea behind including probiotics in some of these products is that, theoretically, ingesting bacteria that contain enzymes that destroy acetaldehyde in the stomach may help prevent hangover symptoms. —Stacey Colino, Time, 22 Aug. 2025

Word History

Etymology

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

First Known Use

1857, in the meaning defined above

Rhymes for acetaldehyde

• acetanilide
• arabinoside
• cycloheximide
• cyclophosphamide
• diethylamide
• dinucleotide
• ferricyanide
• ferrocyanide
• glutaraldehyde
• glyceraldehyde
• hydroperoxide
• interstratified

Medical Definition

acetaldehyde

noun

ac·​et·​al·​de·​hyde ˌas-ə-ˈtal-də-ˌhīd 

: a colorless volatile water-soluble liquid aldehyde C₂H₄O used chiefly in organic synthesis that can cause irritation to mucous membranes