# emulsion

/ɪˈməɫʃən/ (US) · /ɪmˈʌlʃən/ (UK) · CEFR C1 · Noun

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

## Definition

a mixture of two liquids that usually do not mix, like oil and water. In photography, it refers to a thin layer of chemicals on film that reacts to light to create an image.

For teachers: a mixture of two immiscible liquids, such as oil and water, in which one is dispersed in the other. In the context of photography, it refers to a suspension of silver halide crystals in a gelatin emulsion on photographic film.

## Examples

- The photographer used a high-speed emulsion to capture the fast-moving birds.
- The quality of the final print depends largely on the sensitivity and grain structure of the film emulsion.
- Early photographers struggled to stabilize the emulsion on glass plates, leading to the eventual development of more durable celluloid-based films that could withstand the rigors of transportation and storage.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.