lactic acid

noun

Definition of lactic acid 

: a hygroscopic organic acid C3H6O3 present normally especially in muscle tissue as a by-product of anaerobic glycolysis, produced in carbohydrate matter usually by bacterial fermentation, and used especially in food and medicine and in industry

Examples of lactic acid in a Sentence

Recent Examples on the Web

Often people who work out regularly emit more lactic acid, as well as people who have higher metabolic rates. Mackenzie Wagoner, Vogue, "Here’s Why You Are a Mosquito Magnet," 5 July 2018 But by fermenting the milk — as in creating yogurt and cheese — a lot of that lactose morphs into lactic acid, which is much more easily digested. Caron Golden, sandiegouniontribune.com, "Yogurt: Purely homemade," 25 June 2018 Chemical exfoliations use fruit enzymes or acids like glycolic acid, derived from sugar, and lactic acid, which is made from milk. Crystal Martin, New York Times, "Exfoliation Tips for the Best Skin Ever," 25 June 2018 Physical exfoliants are scrubs, which slough away old cells with gritty substances and a touch of elbow grease, whereas chemical exfoliants use dead skin cell melting substances like glycolic or lactic acids to unstick stubborn cells. Lauren Hubbard, Town & Country, "How to Get Glowing Skin," 25 June 2018 When the researchers experimentally altered L. lactis to stop it from producing lactic acid, this protective effect disappeared. Richard Conniff, Scientific American, "New Probiotic Cholera Vaccine Can Outrace the Infection’s Rapid Spread," 13 June 2018 Sunday Riley’s Good Genes, for instance, contains lactic acid, a chemical typically favored by mosquitoes. Katie Heaney, The Cut, "Good News If You Hate Mosquitoes and Love Beauty Serums," 18 May 2018 Playing a fish to exhaustion depletes its energy reserves and causes lactic acid to build up in its tissues, which can add to stress and contribute to death. Saryn Chorney, PEOPLE.com, "National Oceanic Administration and Shark Tagging Program Issues Statement About 'Sexy Shark Wrangler' Amid Backlash," 21 May 2018 Some of the most common acids that are used in chemical peel treatments at FORME are salicylic acid, glycolic acid, lactic acid and mandelic acid. Milwaukee Journal Sentinel, "The clinical advantage of chemical peels," 16 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lactic acid.' 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 lactic acid

1790, in the meaning defined above

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Last Updated

29 Sep 2018

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Time Traveler for lactic acid

The first known use of lactic acid was in 1790

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More Definitions for lactic acid

lactic acid

noun

English Language Learners Definition of lactic acid

: a chemical produced by the body in your muscles during exercise

lactic acid

noun

Medical Definition of lactic acid 

: a hygroscopic organic acid C3H6O3 that is known in three optically isomeric forms:

a or D-lactic acid \ˈdē- \ : the dextrorotatory form present normally in blood and muscle tissue as a product of the anaerobic metabolism of glucose and glycogen

b or L-lactic acid \ˈel- \ : the levorotatory form obtained by biological fermentation of sucrose

c or DL-lactic acid \ˈdē-ˈel- \ : the racemic form present in food products and made usually by bacterial fermentation (as of whey or raw sugar) but also synthetically, and used chiefly in foods and beverages, in medicine, in tanning and dyeing, and in making esters for use as solvents and plasticizers

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More from Merriam-Webster on lactic acid

Spanish Central: Translation of lactic acid

Nglish: Translation of lactic acid for Spanish Speakers

Britannica.com: Encyclopedia article about lactic acid

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