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 The lactic acid in sour cream tenderizes chicken beautifully and also helps crunchy, savory coatings stick to the meat. New York Times, 4 June 2021 The 10 percent vegan lactic acid is an AHA (alpha hydroxy acid) that works to slough away dead skin cells for a brighter, more even complexion. Stephanie Perry, Southern Living, 18 May 2021 The formula features lactic acid and peptides to smooth and brighten your complexion. Jennifer Aldrich, Better Homes & Gardens, 6 Apr. 2021 One of my favorite ways to do so is with Sunday Riley’s cult-fave lactic acid treatment Good Genes ($122), which is, blessedly, pregnancy safe. Cory Baldwin, Forbes, 7 May 2021 Queen Cleopatra bathed in sour milk to reap the benefits of naturally occurring lactic acid, an alpha hydroxy acid, and the Romans and Greeks were known to use corrosive agents such as limestone as a manual exfoliant. Washington Post, 12 Apr. 2021 The enzymes break the PLA down into lactic acid, which microbes in the soil can use as food. Theresa Machemer, Smithsonian Magazine, 23 Apr. 2021 Common AHAs are glycolic acid, lactic acid, mandelic acid, malic, tartaric and citric acid. Washington Post, 12 Apr. 2021 These bacteria produce lactic acid, which creates an acidic microenvironment that allows only a few other bacteria and yeasts to grow. ABC News, 4 Apr. 2021

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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The first known use of lactic acid was in 1790

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Statistics for lactic acid

Last Updated

17 Jun 2021

Cite this Entry

“Lactic acid.” Dictionary, Merriam-Webster, Accessed 24 Jun. 2021.

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

More from Merriam-Webster on lactic acid

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


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