lactic acid

American  

noun

Biochemistry.

1. a colorless or yellowish, syrupy, water-soluble liquid, C 3 H 6 O 3 , produced during muscle contraction as a product of anaerobic glucose metabolism, abundant in sour milk, prepared usually by fermentation of cornstarch, molasses, potatoes, etc., or synthesized: used chiefly in dyeing and textile printing, as a flavoring agent in food, and in medicine.

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lactic acid British  

noun

1. Systematic name: 2-hydroxypropanoic acid.  a colourless syrupy carboxylic acid found in sour milk and many fruits and used as a preservative ( E270 ) for foodstuffs, such as soft margarine, and for making pharmaceuticals and adhesives. Formula: CH 3 CH(OH)COOH

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lactic acid Scientific  

/ lăk′tĭk /

1. A syrupy, water-soluble organic acid produced when milk sours or certain fruits ferment. It is also produced in the body during the anaerobic metabolism of glucose, as in muscle tissue during exercise, where its buildup can cause cramping pains. A synthetic form of lactic acid is used as a flavoring and preservative, in dyeing and textile printing, and in pharmaceuticals. Chemical formula: C ₃ H ₆ O ₃ .

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Etymology

Origin of lactic acid

First recorded in 1780–90

Example Sentences

See Examples For:

lactic acid

“You’ve got lactic acid up to your eyeballs,” Porino said.

From The Wall Street Journal ● Feb. 6, 2026

He added, "We plan to expand international research on kimchi and lactic acid bacteria in relation to immune and metabolic health in the future."

From Science Daily ● Dec. 17, 2025

The lactic acid, after some time, will cause the dough to smell like beer.

From Salon ● Sep. 25, 2025

This stops the stress hormone and lactic acid buildup that can hurt flavor and texture when fish are left to asphyxiate.

From Los Angeles Times ● Jul. 29, 2025

Their shoulders must be rubbed every hour and they must be allowed to shake the lactic acid buildup out of their joints each hour.

From "Woodsong" by Gary Paulsen