calcium carbonate

American  

noun

1. a white, crystalline, water-insoluble, tasteless powder, CaCO 3 , occurring in nature in various forms, as calcite, chalk, and limestone: used chiefly in dentifrices and polishes and in the manufacture of lime and cement.

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calcium carbonate British  

noun

1. a white crystalline salt occurring in limestone, chalk, marble, calcite, coral, and pearl: used in the production of lime and cement. Formula: CaCO 3

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calcium carbonate Scientific  

1. A white or colorless crystalline compound occurring naturally in chalk, limestone, and marble and in the minerals calcite and aragonite. It is used to make toothpaste, white paint, and cleaning powder. Chemical formula: CaCO ₃ .

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Etymology

Origin of calcium carbonate

First recorded in 1870–75

Example Sentences

Some of these animals can photosynthesize like plants; some harvest algae and seawater to make calcium carbonate for their underwater castles; some produce their own light or glow in the dark.

From The Wall Street Journal • Nov. 21, 2025

These single-celled algae, which contain chlorophyll, float in the sunlit layers of the sea and are coated with calcium carbonate plates known as coccoliths.

From Science Daily • Oct. 10, 2025

Garrett stops to describe how the towers of calcium carbonate grew underwater around freshwater springs over thousands of years, then were left exposed as the water dropped.

From Los Angeles Times • Aug. 8, 2025

Some crustaceans, for example, have a hard time developing hard outer shells made of calcium carbonate if the water is too acidic.

From Salon • May 21, 2025

“Oh, stuff like magnesium salts, and alcohol for keeping the Deltas and Epsilons small and backward, and calcium carbonate for bones, and all that sort of thing.”

From "Brave New World" by Aldous Huxley