bromide
n. C / Un. a chemical used in the past to make photos last longer. It was also used in medicine to help people sleep or relax.
n. 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.
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.
From brom- + -ide. First used in the sense “dull person” by Gelett Burgess. Figurative sense ("platitude") by extending the medicating sense through the metaphor of pacifying or placating.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Last updated May 30, 2026