permethrin
noun
per·meth·rin
(ˌ)pər-ˈme-thrən 
: a synthetic pyrethroid C21H20Cl2O3 used especially as an insecticide
Examples of permethrin in a Sentence
Recent Examples on the Web
The analysis identified anywhere from 2 to 11 different insecticides in each nest, including fipronil, which was present in 100% of the nests, and imidacloprid and permethrin in 89% of the nests.
—
Grrlscientist, Forbes, 10 Mar. 2025
However, do not ever spray permethrin directly on your skin.10
4.
—Adrienne Dellwo, Verywell Health, 22 Oct. 2024
Complicating matters further is the fact that lice appear to have evolved some resistance to pyrethrin and permethrin, the active ingredients in many over-the-counter lice shampoos.
—Anna North, Vox, 7 Dec. 2018
People can also decide to treat their clothing, boots and camping gear with permethrin, an insecticide that kills or repels mosquitoes, according to the CDC.
—Rong-Gong Lin Ii, Los Angeles Times, 30 Sep. 2024
See All Example Sentences for permethrin
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Grrlscientist, Forbes, 10 Mar. 2025
However, do not ever spray permethrin directly on your skin.10
4.
—Adrienne Dellwo, Verywell Health, 22 Oct. 2024
Complicating matters further is the fact that lice appear to have evolved some resistance to pyrethrin and permethrin, the active ingredients in many over-the-counter lice shampoos.
—Anna North, Vox, 7 Dec. 2018
People can also decide to treat their clothing, boots and camping gear with permethrin, an insecticide that kills or repels mosquitoes, according to the CDC.
—Rong-Gong Lin Ii, Los Angeles Times, 30 Sep. 2024
See All Example Sentences for permethrin
Cite this Entry
“Permethrin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/permethrin. Accessed 30 Apr. 2025.
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permethrin
noun
per·meth·rin
pər-ˈmeth-rən
: a synthetic pyrethroid pesticide C21H20Cl2O3 used especially against insects, ticks, and mites
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