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Related to alpha-hydroxy acid: lactic acid
n. Abbr. AHA
Any of various acids, such as citric acid or glycolic acid, that contain a hydroxyl group adjacent to the carboxyl group and are often used in exfoliants and other cosmetics.
alpha-hydroxy acidAbbreviation: AHA
Any of a class of water-soluble acids derived from fruit or milk, having a hydroxyl moiety in the first position in the molecule. AHAs are used in chemical peels and other skin care products to remove the outer layer of the epidermis. This chemical exfoliation is promoted for its cosmetic effects on wrinkled or sun-damaged skin.
See also: acid