# halogen

/ˈhæɫədʒən/ (US) · /hˈælədʒən/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/halogen
Updated: 2026-05-20

## Definition

a group of chemical elements that are very reactive and often used in things like light bulbs and cleaning products. They include elements like fluorine, chlorine, and iodine.

For teachers: any of the elements in group 17 of the periodic table, characterized by high reactivity and the tendency to form salts. Includes fluorine, chlorine, bromine, iodine, and astatine.

## Examples

- Chlorine is a common halogen used for disinfecting water.
- The chemist explained that halogens are highly reactive and must be handled with care in the laboratory.
- The unique electronic configuration of halogens allows them to readily accept an additional electron, making them powerful oxidizing agents in various industrial applications.

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