noun, often attributive
cal·​ci·​um | \ ˈkal-sē-əm How to pronounce calcium (audio) \

Definition of calcium

: a metallic chemical element of the alkaline-earth group that occurs naturally only in combination and is essential to cellular functions in all known organisms — see Chemical Elements Table

Examples of calcium in a Sentence

Her doctor said she should eat more foods that are high in calcium, such as milk and cheese.
Recent Examples on the Web These products are not designed with the accurate amounts of imperative nutrition sources like protein, iron, calcium, and other crucial vitamins that babies need. Stefani Sassos, Ms, Rdn, Cso, Cdn, Nasm-cpt, Good Housekeeping, 14 May 2022 Most organic fertilizers also contain additional nutrients like iron or calcium that further feed the health and vibrancy of your grass. Samantha Jones, Better Homes & Gardens, 10 May 2022 The water level has plummeted, leaving ghostly calcium deposits along the lake’s rocky shores. Los Angeles Times, 6 May 2022 The residue contained sulfur and mercury, as well as magnesium, nitrates, phosphorus, calcium (possibly derived from calcium oxide, a component of Greek fire), lead, and iron. Jennifer Ouellette, Ars Technica, 3 May 2022 In terms of other people who may want to consider a multivitamin, Keatley says the most common deficiencies in the U.S. are iron, calcium, and vitamins B12. Allure, 25 Apr. 2022 The particles were not enriched with calcium and strontium, which would be present if the particles were from Earth. Elizabeth Gamillo, Smithsonian Magazine, 13 Apr. 2022 According to the National Institutes of Health, the calcium deposits typically form in and around joints like the knees and elbows, and are difficult to treat — some respond to medication, but others need to be surgically removed. Julie Mazziotta,, 11 Apr. 2022 Because regurgitating valves have structural damage, rather than being gummed up by calcium deposits, TAVR often will not work because the device cannot properly seat itself in the surrounding tissue. Paul Sisson, San Diego Union-Tribune, 27 Feb. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'calcium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of calcium

1808, in the meaning defined above

History and Etymology for calcium

New Latin, from Latin calc-, calx lime

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Time Traveler for calcium

Time Traveler

The first known use of calcium was in 1808

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Dictionary Entries Near calcium



calcium aluminate

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Statistics for calcium

Last Updated

19 May 2022

Cite this Entry

“Calcium.” Dictionary, Merriam-Webster, Accessed 24 May. 2022.

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More Definitions for calcium


cal·​ci·​um | \ ˈkal-sē-əm How to pronounce calcium (audio) \

Kids Definition of calcium

: a silvery soft metallic chemical element that is essential for strong healthy bones


noun, often attributive
cal·​ci·​um | \ ˈkal-sē-əm How to pronounce calcium (audio) \

Medical Definition of calcium

: a silver-white bivalent metallic element that is an alkaline earth metal, occurs only in combination, and is an essential constituent of most plants and animals symbol Ca — see Chemical Elements Table

More from Merriam-Webster on calcium

Nglish: Translation of calcium for Spanish Speakers

Britannica English: Translation of calcium for Arabic Speakers Encyclopedia article about calcium


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