# pesticide

/ˈpɛstəˌsaɪd/ (US) · /pˈɛstɪsˌaɪd/ (UK) · CEFR B2 · Noun

Source: https://englishreference.com/word/pesticide
Updated: 2026-05-07

## Definition

a chemical substance used to kill insects or other small animals that damage crops and plants.

For teachers: a chemical substance used for destroying organisms that are harmful to cultivated plants or to animals.

## Examples

- Farmers use pesticides to protect their crops from insects.
- The local government is encouraging organic farming to reduce the amount of pesticide runoff entering the river system.
- While these pesticides effectively eliminate invasive beetles, environmentalists worry about their long-term impact on the local bee population and the broader ecological balance.

## Usage notes

- Uncountable when referring to the substance in general; countable when referring to specific types or brands of the chemical.

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