calcium carbonate

noun

: a compound CaCO3 found in nature as calcite and aragonite and in plant ashes, bones, and shells and used especially in making lime and Portland cement and as a gastric antacid

Examples of calcium carbonate in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Corals grow their calcium carbonate skeletons by pulling calcium from the ocean water but can substitute the element strontium if needed. — Andrea Thompson, Scientific American, 27 Aug. 2026 Specifically, corals grow one to two centimeters per year by secreting layers of calcium carbonate. — Doyle Rice, USA Today, 27 Aug. 2026 Like trees that produce annual growth rings, corals add skeletal layers of calcium carbonate year after year. — Julia Cole, The Conversation, 27 Aug. 2026 The reefs were made of metal grids and coated in calcium carbonate, and were then fixed to the underwater seawall at Marina Palamós. — Laura Baisas, Popular Science, 30 July 2026 See All Example Sentences for calcium carbonate

Word History

First Known Use

1868, in the meaning defined above

Time Traveler
The first known use of calcium carbonate was in 1868

Rhymes for calcium carbonate

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Browse Nearby Words

calcium carbide
calcium carbonate
calcium channel blocker
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Cite this Entry

“Calcium carbonate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/calcium%20carbonate. Accessed 1 Sep. 2026.

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Kids Definition

calcium carbonate

noun
: a solid substance found in nature as limestone and marble and in plant ashes, bones, and shells and used especially in making lime and portland cement

Medical Definition

calcium carbonate

noun
: a calcium salt CaCO3 that is found in limestone, chalk, marble, plant ashes, bones, and many shells, that is obtained also as a white precipitate by passing carbon dioxide into a suspension of calcium hydroxide in water, and that is used in dentifrices and in pharmaceuticals as an antacid and to supplement bodily calcium stores

More from Merriam-Webster on calcium carbonate

Britannica.com: Encyclopedia article about calcium carbonate

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