aldehyde

American

[al-duh-hahyd] / ˈæl dəˌhaɪd /

noun

Chemistry.

any of a class of organic compounds containing the group −CHO, which yields acids when oxidized and alcohols when reduced.

aldehyde British

/ ˈældɪˌhaɪd, ˌældəˈhɪdɪk /

noun

any organic compound containing the group -CHO. Aldehydes are oxidized to carboxylic acids and take part in many addition reactions
(modifier) consisting of, containing, or concerned with the group -CHO

aldehyde group or radical

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

aldehyde Scientific

/ ăl′də-hīd′ /

Any of a class of highly reactive organic compounds obtained by oxidation of certain alcohols and containing the group CHO. Aldehydes are used in manufacturing resins, dyes, and organic acids.

Other Word Forms

aldehydic

adjective

Etymology

Origin of aldehyde

1840–50; < New Latin al ( cohol ) dehyd ( rogenātum ) dehydrogenated alcohol

Vocabulary lists containing aldehyde

Organic Chemistry

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Example Sentences

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See Examples For:

aldehyde

Further analysis of a representative sample, Fr.9, using ^13C-DEPT NMR revealed the presence of an aldehyde group, confirming earlier findings.

From Science Daily ● Jan. 11, 2026

After a match, “he stank like kerosene, ammonia, aldehyde, sweat. His waterlogged clothes looked like he’d been dunked in the ocean. Foreign hairs from the mat were sticking to his skin.”

From New York Times ● Aug. 23, 2021

You might be trying to get at, for example, an aldehyde called vanillin.

From Washington Post ● Feb. 21, 2019

The names for aldehyde and ketone compounds are derived using similar nomenclature rules as for alkanes and alcohols, and include the class-identifying suffixes -al and -one, respectively:

From Textbooks ● Feb. 14, 2019

Even through the door she can smell him, peppermint, musk, aldehyde.

From "All the Light We Cannot See" by Anthony Doerr

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023