1
: destroying or controlling insects
2
: of or relating to an insecticide

Examples of insecticidal 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.
Consider applying an insecticidal soap or horticultural oil after pruning to smother scale and insect eggs to the dormant roses. — Mary Marlowe Leverette, Southern Living, 10 Sep. 2026 Fragrance-free liquid Castile soap with no additives can be mixed with water and turned into an insecticidal soap. — Ashley Chalmers, The Spruce, 14 Aug. 2026 Their natural enemies live in the garden too; so, don’t spray with any kind of pesticide, oil or insecticidal soap. — Nan Sterman, San Diego Union-Tribune, 1 Aug. 2026 Use Insecticidal Soap Applying an insecticidal soap is a less toxic alternative to conventional pesticides. — Anne Readel, Better Homes & Gardens, 26 July 2026 See All Example Sentences for insecticidal

Word History

First Known Use

1857, in the meaning defined at sense 1

Time Traveler
The first known use of insecticidal was in 1857

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Cite this Entry

“Insecticidal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/insecticidal. Accessed 6 Oct. 2026.

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