# effluent

/ˈɛfɫuənt/ (US) · /ˈɛfluːənt/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/effluent
Updated: 2026-10-14

## Definition

dirty liquid waste that flows out of a factory, farm, or sewage plant into rivers or the sea.

For teachers: liquid waste or sewage discharged from an industrial, agricultural, or municipal source into the environment. Typically refers to treated or untreated outflow entering rivers, lakes, or the sea.

## Examples

- The factory cleans its effluent before release.
- The council fines the plant because its effluent pollutes the nearby river.
- Despite meeting legal limits, the treated effluent still altered downstream chemistry, reducing oxygen levels and threatening sensitive fish populations.

## Usage notes

- Often uncountable in general use; plural 'effluents' for distinct waste streams or sources.

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