# bromide

/ˈbɹoʊˌmaɪd/ (US) · /bɹˈɒmaɪd/ (UK) · CEFR C2 · Noun

Source: https://englishreference.com/word/bromide
Updated: 2026-05-30

## Definition

a chemical used in the past to make photos last longer. It was also used in medicine to help people sleep or relax.

For teachers: a salt of hydrobromic acid, historically used in photographic emulsions and as a sedative in medicine. Often refers to silver bromide in the context of early photography.

## Examples

- The photographer used silver bromide to develop the film.
- Before modern sedatives were available, doctors often prescribed potassium bromide to patients suffering from anxiety or insomnia.
- The transition from silver bromide to more sensitive emulsions marked a significant shift in the speed and quality of photographic film during the late nineteenth century.

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