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

Considering that strontium can replace calcium in calcite’s crystal structure, the mineral effectively locked the radioactive element into a stable form. — Georgina Jedikovska, Interesting Engineering, 3 July 2026

Minerals such as calcium, manganese, and fluoride support bone health, helping to prevent or manage diseases like arthritis and osteoporosis. — Embry Roberts, Martha Stewart, 2 July 2026

Watermelon is a good source of magnesium and potassium and also contains calcium, iron, and folate. — Amber J. Tresca, Verywell Health, 2 July 2026

Shah believes that factors that can impact this include low stomach acid, gut inflammation, high calcium intake along with iron, and thyroid imbalances. — Tatiana Dias, Vogue, 30 June 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