ke·​tone | \ ˈkē-ˌtōn How to pronounce ketone (audio) \

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 How to pronounce ketonic (audio) \ adjective

Examples of ketone in a Sentence

Recent Examples on the Web While the fat is broken down, your breath can smell sweeter thanks to the release of ketones, including acetone, as a byproduct. Courtney Linder, Popular Mechanics, "Your Sweat Can Give Away How Drunk You Are," 12 Dec. 2019 When your body does not have enough carbs to sustain everyday activity, the liver breaks down fat into ketones, which can then be used as energy. Adele Jackson-gibson, Good Housekeeping, "Can You Do Intermittent Fasting While on the Keto Diet?," 26 Nov. 2019 It is thought that eating a 4:1 ratio of fat to carbohydrate forces the body to burn molecules called ketones for energy instead of carbohydrates. Isabel Derera, The Conversation, "CBD and genetic testing provide hope for ‘intractable’ epilepsy in children," 25 July 2019 It should be emphasized that for people with diabetes, however, ketones can build up and lead to diabetic ketoacidosis, a serious medical condition. Molly Kimball,, "The do’s and don’ts of the high-fat, low-carb keto diet: Best of Molly Kimball," 11 June 2019 The exhaust from this, ketones, will not only keep your brain going during those periods of fasting and hunger but will actually improve cognition, grow the connections between neurons, and stave off neurodegeneration. Rahul Jandial, Md,, "The Popular Diet One Neurosurgeon Swears By as a Way to Boost His Brainpower," 5 June 2019 Metabolic switching between glucose and ketones is when cognition is best and degenerative diseases are kept at bay. Rahul Jandial, Md,, "The Popular Diet One Neurosurgeon Swears By as a Way to Boost His Brainpower," 5 June 2019 For an alternative source of energy, your liver will start to convert fat into ketones, which will then be released into the bloodstream and be used by your cells for energy. Karla Walsh, Woman's Day, "The Ultimate Keto Diet Foods List of What You Can (and Can't) Eat," 28 Dec. 2018 This time, the doctor found something called ketones in my urine, which meant my body was breaking down more of itself for energy than is safe. Jenn Morson, Redbook, "A Rare Condition While I Was Pregnant Nearly Killed Me and My Baby," 5 Sep. 2017

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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Time Traveler for ketone

Time Traveler

The first known use of ketone was in 1851

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Statistics for ketone

Last Updated

6 Jan 2020

Cite this Entry

“Ketone.” The Dictionary, Merriam-Webster Inc., Accessed 19 January 2020.

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More Definitions for ketone


ke·​tone | \ ˈkē-ˌtōn How to pronounce ketone (audio) \

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 insert between existing elements

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