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

When it’s combined with the other two hero ingredients in the serum—caffeine (which constricts blood vessels to make pimples look less red) and lactic acid (a pore-clearing and bump-smoothing exfoliant)—it turns into a zit-fighting machine. Ruby Buddemeyer, Marie Claire, "Allies of Skin Promise Keeper Fixed My Acne in 48 Hours," 26 June 2018 Milk is fermented by lactic acid bacteria or curdled by heat or acid from a souring agent like lemon juice or vinegar. New York Times, "A Guide to Soft Fresh Cheeses: Cottage Cheese, Mascarpone and More," 26 June 2018 Since lactic acid can cause muscle soreness, so the Emsculpt process prevents patients from getting too sore. Maggie Maloney, Town & Country, "Everything You Need to Know About Emsulpt," 21 Feb. 2019 The obsession is justifiable: Their milk is loaded with lactic acid, a dermatological wonder that gently exfoliates, can help reduce signs of aging like spots and sallowness, and can increase skin’s ability to retain moisture. Jennifer Goldstein, Marie Claire, "Goat Milk Is the Secret to Beautiful Skin," 29 Nov. 2018 The gel combines sodium lactate (a lactic acid derivative) with niacinamide and hyaluronic acid, to provide exfoliation with a ton of hydration. Hallie Gould, The Seattle Times, "6 top products for smooth summer skin," 26 July 2018 Other acids like lactic acid and salicylic acid can have exfoliating properties that help prevent excess oil and dirt from getting trapped in the follicles, Dr. Nussbaum says. Talia Abbas, SELF, "How to Get Rid of Blackheads on Your Nose, Chin and Forehead," 28 Dec. 2018 BIOSTIMULATORY FILLER Products like, poly-L-lactic acid (brand name: Sculptra) and calcium hydroxylapatite (Radiesse), which volumize skin by gradually stimulating collagen production. Allure, "The Skin-Care Glossary: A Comprehensive Guide to Everything You Need to Know," 17 Aug. 2018 This helps the formula's exfoliating AHAs, like glycolic acid and lactic acid, slough away dead skin cells and smooth skin. Devon Abelman, Allure, "Glow Recipe Launches Reformulated Version of Sold-Out Blueberry Bounce Cleanser," 14 Aug. 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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Statistics for lactic acid

Last Updated

12 May 2019

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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

technical : 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-​ How to pronounce D-lactic acid (audio) \ : 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-​ How to pronounce L-lactic acid (audio) \ : the levorotatory form obtained by biological fermentation of sucrose
c or DL-lactic acid \ ˈdē-​ˈel-​ How to pronounce DL-lactic acid (audio) \ : 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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