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
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Data helped usher in legislation that banned the use of the insecticide, DDT. Kim Bellware The Washington Post, Arkansas Online, 28 Dec. 2025 The substances span a wide range of uses, from flame retardants and fungicides to insecticides and plastic additives. Andrea Margolis, FOXNews.com, 5 Dec. 2025 Most insecticides are not effective against German roaches. Maria Azzurra Volpe, MSNBC Newsweek, 24 Nov. 2025 The Best Moth Repellant In the old days, people used mothballs as an insecticide. Brandee Gruener, Southern Living, 31 Oct. 2025 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

Browse Nearby Words

Cite this Entry

“Insecticide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/insecticide. Accessed 10 Jan. 2026.

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 adjective
Last Updated: - Updated example sentences
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