# calcium

> English word · Noun · IPA /ˈkælsi.əm/ · frequency rank #9,291

## Definitions
1. The chemical element with atomic number 20: a soft, silvery-white alkaline earth metal which occurs naturally as carbonate in limestone and as silicate in many rocks.
2. An atom of this element.

## Etymology
Coined by British chemist Humphry Davy in 1808, from Latin calx (“lime, limestone”) because it occurs in limestone. By surface analysis, calc- + -ium.

## Easily confused with
- **Calum** (https://plainspell.com/en/vs/calcium-vs-calum)
- **Callum** (https://plainspell.com/en/vs/calcium-vs-callum)
- **cadmium** (https://plainspell.com/en/vs/cadmium-vs-calcium)
- **calcite** (https://plainspell.com/en/vs/calcite-vs-calcium)

## Common misspellings (10)
`aclcium`, `caclium`, `calccium`, `calcimu`, `calciumm`, `calcuim`, `calicum`, `callcium`, `ccalcium`, `clacium`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/calcium