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

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Etymology

Origin of pesticide

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

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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

At least nine companies sell pricey pesticide treatments or natural oil sprays for the backyard that are supposed to repel deer, or ticks, sparking an angry debate over whether they also endanger pets and pollinators.

From Los Angeles Times ● Oct. 4, 2026

Labor advocates who have studied pesticide regulation say the oversight gaps and failures to impose stiffer fines underscore the need for more vigilant enforcement.

From Los Angeles Times ● Sep. 24, 2026

The county regulators interpret pesticide safety laws differently, are not required to justify fines and are not mandated to check a company’s statewide compliance history, the audit found.

From Los Angeles Times ● Sep. 24, 2026

In interviews, commissioners lauded California’s enforcement system, saying they think it’s important to have discretion when applying regulations because crops, growing seasons and pesticide use vary from county to county.

From Los Angeles Times ● Sep. 24, 2026

The refuge manager believes that pesticide residues are now building up in the waters of these refuges, being conveyed there by return irrigation flow from heavily sprayed agricultural lands.

From "Silent Spring" by Rachel Carson

But drought, pesticides and habitat destruction triggered an unprecedented collapse that began in 2017, eventually wiping out an estimated 99.5 percent of the Bogong moth population.

From Barron's ● Oct. 2, 2026

Researchers say the technology may also offer a way to reduce water use and reliance on pesticides in strawberry production.

From Science Daily ● Oct. 1, 2026

Because Plant Armor physically prevents insects from feeding on the plants, Olawuyi said the technology could also reduce the amount of conventional pesticides needed in agricultural fields.

From Science Daily ● Oct. 1, 2026

And it is difficult to control with pesticides.

From The Wall Street Journal ● Sep. 19, 2026

There is no reason why it should not serve as a warning that it is no longer sensible to take the “calculated risk” of saturating our environment with pesticides.

From "Silent Spring" by Rachel Carson

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Related Words

• defoliant
• fungicide
• insecticide

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