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

Sunday Riley Game Changer Kit This is a seriously good deal on a killer skincare set, containing a gentle cleanser and cult favorite lactic acid serum, that rarely goes on sale. Sara Hendricks, USA TODAY, "5 of the best beauty deals you can get this Prime Day," 16 July 2019 And compression therapy is said to reduce inflammation and fluid collection, help remove toxins such as lactic acid, improve blood circulation, prevent and eliminate varicose veins, and strengthen loose skin caused by pregnancy or obesity. Tyra Mcclung,, "Afloat In Avon: Wellness Therapy Promotes Relaxation, Relieves Sports Injuries," 2 July 2019 These dual-sided pads provide both chemical and physical exfoliation through lactic acid, and will help me get baby soft skin. Tiffany Dodson, SELF, "Ulta Is Having a 50 Percent Off Sale on Skin-Care—Here’s Everything I Want," 18 Jan. 2019 The natural function of this bug is to break down lactic acid, which is produced by the body during intense exercise and is known to lead to muscle fatigue and soreness. Susan Scutti, CNN, "Could the poo of elite athletes provide an ingredient to improve physical performance?," 25 June 2019 Cultured Added to pasteurized cream, live bacterial cultures release lactic acid while the mixture thickens and develops flavor (through fermentation) before being churned into butter. Lucinda Scala Quinn, Washington Post, "How to put fancy, high-fat butter to its best use," 21 June 2019 That includes people with higher body temperatures and those who produce more carbon dioxide or lactic acid, Irwin said. Katherine Rosenberg-douglas,, "Mosquitoes in northern Illinois should peak this weekend, but West Nile threat to stick around," 6 June 2019 The breakdown produces lactic acid, which naturally preserves and prevents the growth of harmful bacteria in the cabbage. Audrey Bruno, SELF, "Here's How to Make Sauerkraut," 30 Oct. 2018 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

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

21 Jul 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


English Language Learners Definition of lactic acid

technical : 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-​ 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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Spanish Central: Translation of lactic acid

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

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an act or instance of editing or removing

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