ketone

noun

ke·​tone ˈkē-ˌtōn 

: any of a class of organic compounds (such as acetone) characterized by a carbonyl group attached to two carbon atoms

ketonic

kē-ˈtä-nik 

adjective

Examples of ketone in a Sentence

Recent Examples on the Web

The approach works by feeding the brain ketones instead of forcing the body to break down muscle for glucose. — Hanna Wickes, Fort Worth Star-Telegram, 17 Aug. 2026

The goal was to maintain weight while inducing nutritional ketosis — a metabolic state in which the body produces and uses ketones for energy because carbohydrate intake is low enough to shift metabolism toward fat burning. — Angelica Stabile, FOXNews.com, 4 June 2026

The company is also working on implementing other measures of metabolic health by monitoring ketones and potassium — though that technology is still a ways out. — Noelle Harff, San Diego Union-Tribune, 15 May 2026

The body may make other fuel sources, like ketones, which can be an additional danger related to hyperglycemia. — Dr. Brooke Redmond, Boston Herald, 3 May 2026

Word History

Etymology

borrowed from German Keton, coinage based on Aceton acetone

Note: The German term Keton was apparently the coinage of the chemist Leopold Gmelin (1788-1853), who introduced it in Handbuch der organischen Chemie, 1. Band, 4. Auflage (Heidelberg, 1848), p. 40 passim. Gmelin characterized ketones as "Acetone im allgemeinen" ("acetones in general"), acetone being the smallest and simplest ketone.

First Known Use

1851, in the meaning defined above

Phrases Containing ketone

• ketone body
• methyl ethyl ketone

Medical Definition

ketone

noun

ke·​tone ˈkē-ˌtōn 

: an organic compound (as acetone) with a carbonyl group attached to two carbon atoms