ke·tone | \ˈkē-ˌtōn \

Definition of ketone 

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

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Other Words from ketone

ketonic \kē-ˈtä-nik \ adjective

Examples of ketone in a Sentence

Recent Examples on the Web

Some keto adherents also report having pretty atrocious breath, which might be caused by the presence of acetone, a ketone and by-product of fat metabolism, in exhaled breath. Daniel Schultz, Ms, SELF, "Here’s What You Should Know Before Going on the Keto Diet," 16 Apr. 2018 The byproduct is ketones, which can be used for fuel instead. Sandy Bauers,, "Good fats, bad fats, and why the ketogenic diet matters," 13 July 2018 There will also be add-ons, like a multivitamin and a ketone supplement. Christopher Cason, GQ, "The Real-Life Diet of "Longest Swim" Star Ben Lecomte, Who Is About to Swim Across the Pacific Ocean," 5 June 2018 Some of the chemicals, known as esters and ketones, are typically used in the flavoring and fragrance industries, while others are used in food processing and incorporated in cleaning products. Don Behm, Milwaukee Journal Sentinel, "Milorganite mystery: Homegrown fertilizer's new scent has officials sleuthing to identify source of change," 30 Apr. 2018 These ketones can be used by the body and brain for energy. Sheah Rarback, miamiherald, "Research shows ketogenic diet could be helpful for diabetics | Miami Herald," 16 Apr. 2018 When carbohydrate intake is dramatically reduced the body starts breaking down fats in the liver and releasing ketones. Sheah Rarback, miamiherald, "Research shows ketogenic diet could be helpful for diabetics | Miami Herald," 16 Apr. 2018 Health contributing nutrition editor Cynthia Sass warns that the biggest risk associated with a keto diet is the potential for ketoacidosis, which occurs when excess ketones build up and blood becomes acidic and can be life-threatening. Blake Bakkila,, "7 Keto-Friendly Recipes People Are Loving on Pinterest," 8 Mar. 2018 Even people with type 2 diabetes following a ketogenic diet should regularly test their blood sugar and ketone levels to prevent DKA. Amy Gorin, NBC News, "What is the keto diet — and is it right for you?," 22 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ketone.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ketone

1851, in the meaning defined above

History and Etymology for ketone

German Keton, alteration of Aceton acetone

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Statistics for ketone

Last Updated

1 Sep 2018

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Time Traveler for ketone

The first known use of ketone was in 1851

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More Definitions for ketone


ke·tone | \ˈkē-ˌtōn \

Medical Definition of ketone 

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

More from Merriam-Webster on ketone Encyclopedia article about ketone

Comments on ketone

What made you want to look up ketone? Please tell us where you read or heard it (including the quote, if possible).


to reject or criticize sharply

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