lactic acid

carboxylic acid produces at the end of the process of energy creation in cells

Lactic acid (IUPAC systematic name: 2-hydroxypropanoic acid), also known as milk acid, is a chemical compound that plays a role in several biochemical processes. It was first isolated in 1780 by a Swedish chemist, Carl Wilhelm Scheele, and is a carboxylic acid with a chemical formula of C3H6O3. It has a hydroxyl group adjacent to the carboxyl group, making it an alpha hydroxy acid (AHA). In solution, it can lose a proton from the acidic group, producing the lactate ion CH3CH(OH)COO−. It is miscible with water or ethanol, and is hygroscopic.
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Lactic acid /lac·tic ac·id/ CH3CHOHCOOH, a compound formed in the body in anaerobic metabolism of carbohydrate and also produced by bacterial action [more]Lactic acid - Community and Resources

Noun
1. a clear odorless hygroscopic syrupy carboxylic acid found in sour milk and in many fruits
(hypernym) carboxylic acid

a byproduct of carbohydrate metabolism (anaerobic metabolism) that plays a role in several biochemical processes; produced (for example) as a result of anaerobic respiration in muscles and red blood cells when glycogen rather than oxygen is used as an energy source for respiration.