[ 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.

Origin of aldehyde

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


al·de·hy·dic, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Examples from the Web for aldehyde

British Dictionary definitions for aldehyde

/ (ˈældɪˌhaɪd) /


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 -CHOaldehyde group or radical

Derived forms of aldehyde

aldehydic (ˌældəˈhɪdɪk), adjective

Word Origin for aldehyde

C19: from New Latin al (cohol) dehyd (rogenātum) dehydrogenated alcohol
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

Medical definitions for aldehyde

[ ăldə-hīd′ ]


Any of a class of reactive organic chemical compounds obtained by oxidation of primary alcohols, characterized by the common group CHO, and used in the manufacture of resins, dyes, and organic acids.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for aldehyde

[ ăldə-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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.