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.
Next, slowly approach the nest and apply the aerosol insecticide directly into the nest opening, following the product label’s instructions. — Michelle Mastro, Martha Stewart, 5 Aug. 2026 This powerful insecticide should never be applied directly on skin. — Emily Kay Votruba, EverydayHealth.com, 5 Aug. 2026 Mosquitoes were set to be treated with Zenivex E20, one of the safest insecticides approved for use by the state department of environmental protection, according to Allegheny County Health Department. — Finch Walker, USA Today, 4 Aug. 2026 Apply a minor nutrient spray and insecticide to citrus at each flush of new growth. — Tom MacCubbin, The Orlando Sentinel, 1 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 13 Aug. 2026.

Copy Citation

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
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