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

The citric acid that adds tang to sugary drinks and the silica that gives toothpaste its grit are made with it, too.

From The Wall Street Journal • May 9, 2026

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

The team measured the responses of 143 American adults to various levels of citric acid in water.

From Science Daily • Apr. 29, 2024

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

From "The Omnivore's Dilemma" by Michael Pollan