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 Use repellents that contain 20 to 30 percent DEET on exposed skin and clothing for protection that lasts up to several hours. Use products that contain permethrin to treat clothing and gear, such as boots, pants, socks and tents. Ashley Welch, CBS News, "Diseases spread by ticks hit record level in U.S.," 14 Nov. 2018 Loomed of yarn treated with permethrin, anti-bug socks are the foundation for a full-body shield against the tiniest invaders. T. Edward Nickens, Field & Stream, "The Best Clothing, Chemicals, and Sprays to Prevent Tick and Chigger Bites," 13 July 2020 These lightweight pants are easy to pack and wash (so definitely bring them on your camping getaway), and are treated with scent-free permethrin for mosquito protection that lasts for up to 70 washes. Andrea Beck, Better Homes & Gardens, "5 Wearable Mosquito Repelling Products That Keep Pesky Biting Bugs at Bay," 6 Aug. 2020 Treating clothing and shoes with the insecticide permethrin can be effective, too, especially when combined with a DEET-containing insect repellent used on the skin. Jen Rose Smith, CNN, "Corona with Lyme? Warmer weather means it's time to be tick aware," 25 May 2020 Treat clothing and gear with products that contain .5 percent permethrin. Natalie Dreier, ajc, "Tick bite causes girl to become temporarily paralyzed," 8 June 2018 In general, oral meds aren't advised for pets who have seizures, and cats should never wear collars containing permethrin, which can be toxic to them. Karen Asp, Better Homes & Gardens, "Bug Off: How to Prevent Get Rid of Fleas and Ticks on Your Pet," 7 Apr. 2020 Don't apply repellents containing permethrin directly to skin. Sarah Ladd, The Courier-Journal, "Louisville officials advise caution with mosquitoes after West Nile virus death," 17 Oct. 2019 The repellent/insecticide permethrin can be used on clothing to protect through several washes. Leada Gore |, al, "Mosquito-borne virus kills 1 in Alabama: What to know about EEE," 28 Oct. 2019

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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Time Traveler for permethrin

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The first known use of permethrin was in 1975

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Cite this Entry

“Permethrin.” Dictionary, Merriam-Webster, Accessed 30 Nov. 2020.

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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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