per·​meth·​rin | \ (ˌ)pər-ˈme-thrən How to pronounce permethrin (audio) \

Definition of permethrin

: a synthetic pyrethroid C21H20Cl2O3 used especially as an insecticide

Examples of permethrin in a Sentence

Recent Examples on the Web

The Massachusetts Department of Public Health particularly recommends a repellent with permethrin, picaridin, IR3535, DEET or oil of lemon eucalyptus. Hanna Krueger,, "‘It decimated his brain’: Woman recounts husband’s battle with EEE," 27 Aug. 2019 As such, the CDC recommends wearing bug spray when spending time outside, and treating outdoor gear with insect-repelling permethrin. Jamie Ducharme, Time, "Mosquito-Borne West Nile Virus Soared in 2018, According to CDC Data," 9 Aug. 2019 Also, consider treating things like your clothes, shoes, and camping gear with products that contain 0.5 percent of the insecticide permethrin, which stays effective for several washes, the CDC says (or buy gear pre-treated with this chemical). Patia Braithwaite, SELF, "8 Tick-Borne Illnesses That Aren’t Lyme Disease," 26 July 2019 These insects are tough to control, but regular applications of permethrin or bifenthrin will help minimize the damage. Dan Gill,, "Protect tomatoes from these diseases and pests," 13 Apr. 2019 Those pesticides included atrazine (26%), chlorpyrifos (59%), cypermethrin (49%), diazinon (60%), and permethrin (46%). Rebekah Tuchscherer, USA TODAY, "Study finds residue of pesticides, antibiotics and growth hormone in non-organic milk," 26 June 2019 According to a statement from ExOfficio, home permethrin treatments are riskier due to chemical runoff and overuse, but that’s not the case with pretreated garments. Megan Michelson, Outside Online, "DEET Will Kill Your Gore-Tex Jacket," 11 June 2018 To fight back the swarms, the owner doused the sheep in a wash of the insecticide permethrin. Beth Mole, Ars Technica, "US invaded by savage tick that sucks animals dry, spawns without mating," 8 Aug. 2018 Spray insect repellent with deet or permethrin and wear long sleeves and pants to help protect your skin from these blood-drinking parasites. Caroline Picard, Good Housekeeping, "QUIZ: Can You Identify These Dangerous Summer Plants and Bugs?," 3 Aug. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'permethrin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of permethrin

1975, in the meaning defined above

History and Etymology for permethrin

per- + methyl + pyrethrin

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Dictionary Entries near permethrin



per mensem




per mill

Statistics for permethrin

Last Updated

9 Sep 2019

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The first known use of permethrin was in 1975

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More Definitions for permethrin


per·​meth·​rin | \ pər-ˈmeth-rən How to pronounce permethrin (audio) \

Medical Definition of permethrin

: a synthetic pyrethroid pesticide C21H20Cl2O3 used especially against insects, ticks, and mites

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