citric acid

American  

noun

1. a white, crystalline, water-soluble powder, C 6 H 8 O 7 ⋅H 2 O, a tribasic acid having a strong acidic taste, an intermediate in the metabolism of carbohydrates occurring in many fruits, especially limes and lemons, obtained chiefly by fermentation of crude sugar or corn sugar: used chiefly in the flavoring of beverages, confections, and pharmaceuticals.

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citric acid British  

noun

1. a water-soluble weak tribasic acid found in many fruits, esp citrus fruits, and used in pharmaceuticals and as a flavouring ( E330 ). It is extracted from citrus fruits or made by fermenting molasses and is an intermediate in carbohydrate metabolism. Formula: CH 2 (COOH)C(OH)(COOH)CH 2 COOH

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citric acid Scientific  

/ sĭt′rĭk /

1. A white, odorless acid that has a sour taste and occurs widely in plants, especially in citrus fruit, and is formed during the Krebs cycle. It is used in medicine and as a flavoring. Ions of citric acid are a by-product of the metabolism of carbohydrates during the Krebs cycle. Chemical formula: C ₆ H ₈ O ₇ .

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Etymology

Origin of citric acid

First recorded in 1805–15

Example Sentences

Workers in hazmat suits carefully weigh out magnesium citrate - a compound made by mixing the mineral with citric acid - into shiny, steel containers.

From BBC • Oct. 24, 2025

They’re also coated in a ton of citric acid.

From Salon • Oct. 21, 2025

Nickel, cobalt, and manganese enter the solution, where they are bound into stable complexes by the citric acid anions.

From Science Daily • Nov. 15, 2024

“The PH4 gene is important for citric acid accumulation of fruits for both Citrus and Citrus relatives,” Xu says.

From Scientific American • Oct. 11, 2023

Even the citric acid that keeps the nugget “fresh” is made from corn.

From "The Omnivore's Dilemma" by Michael Pollan