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

Medication, exercise, and calcium and vitamin D supplements are often used for prevention and treatment. — Ayesha Gulzar, Verywell Health, 31 July 2026

Mistakes to Avoid Using yogurt to introduce beneficial microbes and calcium to your soil is a fantastic way to improve your tomatoes’ health. — Sj McShane, Martha Stewart, 29 July 2026

These and other brassicas (Brassica oleracea) will compete with jalapeños for similar nutrients like nitrogen and calcium. — Karen Brewer Grossman, Southern Living, 28 July 2026

One is a coronary artery calcium scan, a specialized CT scan that looks for calcified plaque in the arteries supplying the heart. — Katia Hetter, CNN Money, 27 July 2026

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