# contaminate

/kənˈtæməˌneɪt/ (US) · /kəntˈæmɪnˌeɪt/ (UK) · CEFR B2 · Verb

Source: https://englishreference.com/word/contaminate
Updated: 2026-05-20

## Definition

to make something impure or dirty by mixing it with something harmful or unwanted. You use this when you talk about food, water, or air being ruined by a bad substance.

For teachers: to make something impure or less pure by the addition of a foreign or harmful substance. Transitive — requires a direct object.

## Examples

- The factory waste might contaminate the local river.
- If you leave the food out in the sun, it will contaminate the rest of the batch.
- Environmental scientists are concerned that the chemical spill could contaminate the groundwater, making the surrounding land unsuitable for future agricultural use.

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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.