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.
Use liquid insecticides to drench ant hills and kill ants instantly. Karen Brewer Grossman, Southern Living, 18 June 2026 One active ingredient is spinosad, a natural insecticide approved by the USDA for use in organic gardening. Olivia McIntosh, Martha Stewart, 17 June 2026 There are no insecticides that will control the larva of this inconspicuous grayish-brown moth. Mary Marlowe Leverette, The Spruce, 17 June 2026 If needed, a general garden insecticide made for use on ornamental plants would control the ants and scale following label instructions. Tom MacCubbin, The Orlando Sentinel, 13 June 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

Browse Nearby Words

Cite this Entry

“Insecticide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/insecticide. Accessed 22 Jun. 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
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