calcium

noun

cal·​ci·​um ˈkal-sē-əm 

often attributive

: 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

Research shows that herring are packed with vitamin E, vitamin D, and B12, as well as minerals like selenium, iodine, calcium, and iron.10 Herring is low in toxins like lead, cadmium, and mercury, making herring a nutritious and safe seafood option to add to your diet. —Jillian Kubala, Health, 8 July 2025

Astronomers have now found this kind of calcium fingerprint in a supernova’s remains. —Laura Baisas, Popular Science, 2 July 2025

Astronomers predicted that if a double detonation had occurred, the remnant of the supernova would contain two separate shells of calcium. —Jamie Carter, Forbes.com, 2 July 2025

The coronary calcium scan, a painless CT scan that evaluates the risk of heart disease by measuring calcium deposits in the coronary arteries, has been proven to save countless lives. —Bryant Stamford, The Courier-Journal, 2 July 2025

Word History

Etymology

New Latin, from Latin calc-, calx lime

First Known Use

1808, in the meaning defined above

Phrases Containing calcium

• calcium carbide
• calcium carbonate
• calcium channel blocker
• calcium chloride
• calcium citrate
• calcium cyanamide
• calcium gluconate
• calcium hydroxide
• calcium hypochlorite
• calcium oxalate
• calcium oxide
• calcium phosphate
• calcium silicate
• calcium sulfate

Rhymes for calcium

• dicalcium
• tricalcium

Kids Definition

calcium

noun

cal·​ci·​um ˈkal-sē-əm 

: a silver-white soft metallic element that is found only in combination with other elements (as in limestone) and is one of the necessary elements making up the bodies of most plants and animals see element

Etymology

derived from Latin calc-, calx "lime" — related to calculate, chalk

Medical Definition

calcium

noun

cal·​ci·​um ˈkal-sē-əm 

often attributive

: 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