# boron

/ˈbɔˌɹɑn/ (US) · /bˈɔːɹɒn/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/boron
Updated: 2026-05-19

## Definition

a chemical element that is a solid metal but is not very hard. It is used in things like glass and medicine to help plants grow.

For teachers: a metallic chemical element with the symbol B and atomic number 5. It is a metalloid with properties intermediate between metals and non-metals, often used in the production of glass and ceramics.

## Examples

- The plant needs boron to grow healthy fruit.
- Engineers added boron to the steel alloy to increase its strength and resistance to high temperatures.
- While boron is essential for plant development, its presence in soil must be carefully managed because it can be toxic to crops at concentrations higher than those required for growth.

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