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 Starting with the Vitamin C + Peptide Face Serum, which is crafted with vitamin C and lactic acid to brighten and smooth skin. Angela Trakoshis, Allure, 13 July 2022 The key to keeping brittle nails strong is to keep them hydrated with an efficacious hand cream, like this GH Beauty lab test-winning formula from Eucerin, containing key ingredients like urea and lactic acid. Danusia Wnek, Good Housekeeping, 29 June 2022 Lactate Is Your Friend Lactate, or lactic acid as it is commonly known, gets a bad rap thanks to some faulty science from the 1970′s. Jeff Gaudette, Outside Online, 3 Oct. 2018 Its Primary Cream, a light formula that soothes and strengthens, is particularly well suited for acne-prone skin because of its inclusion of panthenol (also known as vitamin B5) and lactic acid. New York Times, 16 June 2022 There are only four ingredients; glycerin, decyl glucoside, water and lactic acid. Grooming Playbook, The Salt Lake Tribune, 3 June 2022 The old paradigm: lactic acid is a corrosive byproduct of hard exercise that makes your muscles burn and eventually brings you to a halt. Alex Hutchinson, Outside Online, 14 Apr. 2020 The bacteria will feed, release carbon dioxide and dispel lactic acid – taking water and acidifying it to drop the pH level. Aly Walansky, Forbes, 25 June 2022 Jarro-Dophilus Women’s proprietary strains produce lactic acid and hydrogen peroxide (H2O2), which have been shown in clinical trials to lower vaginal pH and foster a more acidic bacterial environment. The Salt Lake Tribune, 25 May 2022 See More

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.

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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Dictionary Entries Near lactic acid


lactic acid

lactic acid bacterium

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Last Updated

4 Aug 2022

Cite this Entry

“Lactic acid.” Dictionary, Merriam-Webster, Accessed 9 Aug. 2022.

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More Definitions for lactic acid

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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