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

If this is the case, then the greater abundances of calcium and aluminum in the farther part of the circumplanetary disk should lead to a thicker crust for the lunar far side as compared to the near side. —Big Think, 26 Nov. 2025

Adequate Vitamin D is necessary for the body to absorb calcium properly in the gut. —Patty Weasler, Verywell Health, 26 Nov. 2025

Electrolytes are essential minerals, including sodium, potassium, calcium, and magnesium, that help your body maintain fluid balance, support muscle function, and regulate nerve signals. —Lindsay Curtis, Health, 20 Nov. 2025

Most Americans need to increase their intake of dietary fiber, calcium, vitamin D, and potassium, the agency notes. —Youri Benadjaoud, ABC News, 19 Nov. 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