[ kee-tohn ]
/ ˈki toʊn /

noun Chemistry.

any of a class of organic compounds containing a carbonyl group, CO, attached to two alkyl groups, as CH3COCH3 or CH3COC2H5.


containing the ketone group.

Nearby words

  1. ketol,
  2. ketole,
  3. ketolysis,
  4. ketolytic,
  5. ketonaemia,
  6. ketone body,
  7. ketone group,
  8. ketonemia,
  9. ketonic,
  10. ketonuria

Origin of ketone

1850–55; < German Keton, aphetic alteration of Aceton acetone

Related formske·ton·ic [ki-ton-ik] /kɪˈtɒn ɪk/, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for ketone

British Dictionary definitions for ketone


/ (ˈkiːtəʊn) /


any of a class of compounds with the general formula R′COR, where R and R′ are alkyl or aryl groupsSee also acetone
Derived Formsketonic (kɪˈtɒnɪk), adjective

Word Origin for ketone

C19: from German Keton, from Aketon acetone

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

Word Origin and History for ketone



chemical group, 1851, from German keton, coined in 1848 by German chemist Leopold Gmelin (1788-1853) from German Aketon, from French acétone (see acetone). Its comb. form is keto-.

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for ketone


[ kētōn′ ]


Any of a class of organic compounds having a carbonyl group linked to a carbon atom in each of two hydrocarbon radicals.

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for ketone


[ kētōn′ ]

Any of a class of organic compounds having the general formula RCOR, where R and R are hydrocarbon radicals that are both attached to the carbon atom of the carbonyl (CO) group. Acetone is a ketone.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.