lactic acid


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

Unlike the original myBlu flavor pod range, which used freebase nicotine, the myBlu Intense flavor pods contain nicotine salts that are created by combining freebase nicotine with lactic acid. Rachel Becker, The Verge, "Juul’s nicotine salts are dominating the market — and other companies want in," 21 Nov. 2018 This cleanser contains vegan lactic acid (derived from beets) that gently exfoliates, and seaweed that hydrates and balances for a glowing AF complexion. Kara Wahlgren, Seventeen, "8 Tricks for Getting Rid of Pimples (Almost) Overnight," 9 July 2018 But this lightweight formula contains something called ethyl lactyl retinoate, a proprietary blend of lactic acid and retinoids, that works to slowly, gently, and effectively smooth skin and fade discoloration with continued use. Chloe Metzger, Marie Claire, "The 5 Truly Excellent Beauty Products I'm Loving This Week," 10 Oct. 2018 Enter, Skinfix's Renewing Scrub and Renewing Cream, a one-two punch of skin-smoothing glycolic and lactic acids, plus other alpha hydroxy acids, to help minimize the appearance of rough, bumpy skin. Karina Hoshikawa, Allure, "Skinfix's Renewing Body Scrub & Cream Combo Is the Most Effective Keratosis Pilaris Treatment I've Ever Used," 27 Aug. 2018 And someone with a higher resting heart rate produces more carbon dioxide and more lactic acid, attracting even more mosquitos, says Day. Mackenzie Wagoner, Vogue, "Here’s Why You Are a Mosquito Magnet," 5 July 2018 First, to create the lactic acid sourness, Spangalang boils the wort (unfermented liquid with sugars from the barley) for just 10 minutes to sanitize it. Matt Allyn, Popular Mechanics, "How The Perfect Pickle Beer Is Made," 18 Oct. 2016 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,, "Yogurt: Purely homemade," 25 June 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

8 Dec 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


English Language Learners Definition of lactic acid

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

lactic acid


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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Spanish Central: Translation of lactic acid

Nglish: Translation of lactic acid for Spanish Speakers Encyclopedia article about lactic acid

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