insecticide

noun

in·​sec·​ti·​cide in-ˈsek-tə-ˌsīd How to pronounce insecticide (audio)
plural insecticides
Synonyms of insecticidenext
: an agent that destroys one or more species of insects
broadly : an agent that destroys insects as well as other small pests (such as mites or nematodes)
Aphids, mealybugs, and cyclamen mites are all common problems and can be controlled with any low-toxicity insecticide sold specifically for houseplants. —Horticulture

Examples of insecticide in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The department added that is has sprayed insecticide in 15 different community areas over the last several weeks. — Mary Kekatos, ABC News, 1 Sep. 2026 The Appalachian Trail Conservancy is fighting that plague by injecting some ash trees with an insecticide to give them a chance at survival. — Amanda Swinhart, Los Angeles Times, 31 Aug. 2026 Insecticides Spraying feeders with insecticides may seem like a smart way to keep pests away from bird seed, but these products can cause more harm than good. — Madeline Buiano, Martha Stewart, 29 Aug. 2026 These crops have fewer pests, or where needed, they can be picked off or treated with natural insecticides. — Tom MacCubbin, The Orlando Sentinel, 22 Aug. 2026 See All Example Sentences for insecticide

Word History

Etymology

International Scientific Vocabulary

First Known Use

1865, in the meaning defined above

Time Traveler
The first known use of insecticide was in 1865

Rhymes for insecticide

See All Rhymes for insecticide

Browse Nearby Words

insecticidal
insecticide
insecticolous
See all Nearby Words

Cite this Entry

“Insecticide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/insecticide. Accessed 6 Sep. 2026.

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Kids Definition

insecticide

noun
in·​sec·​ti·​cide in-ˈsek-tə-ˌsīd How to pronounce insecticide (audio)
: a chemical used to kill insects
insecticidal
(ˌ)in-ˌsek-tə-ˈsīd-ᵊl
adjective

Medical Definition

insecticide

noun
in·​sec·​ti·​cide in-ˈsek-tə-ˌsīd How to pronounce insecticide (audio)
: an agent that destroys insects
insecticidal
(ˌ)in-ˌsek-tə-ˈsīd-ᵊl How to pronounce insecticide (audio)
adjective

More from Merriam-Webster on insecticide

Thesaurus: All synonyms and antonyms for insecticide

Britannica.com: Encyclopedia article about insecticide

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