pesticide

American  

[pes-tuh-sahyd] / ˈpɛs təˌsaɪd /

noun

pesticides plural

1. a chemical preparation for destroying plant, fungal, or animal pests.

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pesticide British  

/ ˈpɛstɪˌsaɪd /

noun

1. a chemical used for killing pests, esp insects and rodents

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pesticide Scientific  

/ pĕs′tĭ-sīd′ /

1. A chemical used to kill harmful animals or plants. Pesticides are used especially in agriculture and around areas where humans live. Some are harmful to humans, either from direct contact or as residue on food, or are harmful to the environment because of their high toxicity, such as DDT (which is now banned in many countries). Pesticides include fungicides, herbicides, insecticides, and rodenticides.

2. See more at fungicide herbicide insecticide

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Other Word Forms

Derived Forms

• pesticidal
  adjective

Inflected Forms

Nouns

• pesticides
  plural

Etymology

Origin of pesticide

First recorded in 1935–40; pest + -i- + -cide

Explanation

A pesticide is a bug-killing poison. You may have to resort to using a pesticide to battle the ants that have invaded your kitchen, even if you hate killing any creature. Pesticides are most often used to ward off insects or small animals living uninvited in a person's house, or in a garden or on a farm, when they are nibbling on plants or flowers. The Latin suffix cide means "killer," and in pesticide, it's combined with the English word pest, which means just what it sounds like — a troublesome annoyance.

Example Sentences

See Examples For:

pesticide pesticides

DDT is a pesticide so dangerous to the environment that it was banned worldwide more than 50 years ago, with rare exceptions; its effects are still traceable in the environment today.

From Los Angeles Times ● Jul. 15, 2026

Instead, they suspect pesticide exposure could help explain the surprising pattern.

From Science Daily ● Jul. 13, 2026

Department of Agriculture funded study, worker bumblebees were exposed to low doses of the pesticide before researchers examined changes in their gene expression.

From Science Daily ● Jul. 10, 2026

These results suggest that the pesticide may contribute to Parkinson's disease by preventing cells from clearing away harmful material, allowing toxic proteins to build up over time.

From Science Daily ● Jun. 28, 2026

Maybe I’m being affected by the pesticide residual.

From "Challenger Deep" by Neal Shusterman

The company is the largest seller of pesticides in the U.S. and a major supplier of crop seeds, competing with Corteva and Bayer to sell farmers the supplies they need.

From The Wall Street Journal ● Jul. 1, 2026

Scientists have long suspected that some chemicals used in agriculture could harm the nervous system, but identifying specific pesticides and understanding how they affect the brain has been challenging.

From Science Daily ● Jun. 28, 2026

They were looking for a steady source of raw milk at a time when consumers were waking up to the risks of food contaminated by additives, fertilizers and pesticides.

From Salon ● Jun. 22, 2026

A boy and girl stand amid rows of crops and point at a frowning sun as an airplane sprays pesticides.

From Los Angeles Times ● Jun. 19, 2026

The organic food in stores like Whole Foods is organic because it is grown without chemical fertilizers or pesticides.

From "The Omnivore's Dilemma" by Michael Pollan

Related Words

• defoliant
• fungicide
• insecticide