# contaminant

/kənˈtæmənənt/ (US) · /kəntˈæmɪnənt/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/contaminant
Updated: 2026-10-18

## Definition

something harmful or dirty that gets into water, food, or air and makes it unsafe to use. You see this word in news about pollution and food safety.

For teachers: an unwanted substance that makes another material impure, often rendering food, water, or air unsafe. Typically refers to trace chemical, biological, or physical agents introduced accidentally or through pollution.

## Examples

- This filter removes contaminants from tap water.
- The factory tests its wastewater daily to ensure no chemical contaminants reach the nearby river.
- Investigators traced the food poisoning outbreak to bacterial contaminants introduced during packaging, prompting a nationwide recall and stricter hygiene controls.

## Synonyms

pollutant, impurity, toxin

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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.