# strontium

/ˈstɹɑntiəm/ (US) · /stɹˈɒntiəm/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/strontium
Updated: 2026-10-18

## Definition

a soft silver-white metal found in nature, used to make bright red colour in fireworks and flares.

For teachers: a soft, silvery-white alkaline-earth metal, chemical element with symbol Sr and atomic number 38, highly reactive and burning with a bright crimson flame.

## Examples

- Fireworks use strontium to make a bright red colour.
- The lab stores strontium carefully because it reacts quickly with air and water.
- Geologists measure strontium ratios in ancient teeth to trace where people lived and travelled.

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