per·​meth·​rin (ˌ)pər-ˈme-thrən How to pronounce permethrin (audio)
: a synthetic pyrethroid C21H20Cl2O3 used especially as an insecticide

Examples of permethrin in a Sentence

Recent Examples on the Web The permethrin spray bonds to fabric fibers for up to 6 weeks or through 6 washings without staining or damaging clothing, fabrics, plastics, or outdoor gear. Karthika Gupta, Travel + Leisure, 21 Mar. 2024 Treating clothing and gear with permethrin (a broad-spectrum insecticide and insect repellent). Alyssa Hui, Verywell Health, 23 Feb. 2024 Items treated with permethrin can have effects that last for weeks or throughout several wash cycles. Steven Rowe, Health, 28 Aug. 2023 And treating clothing and footwear with an insecticide called permethrin is highly effective. Beth Teitell,, 27 July 2023 Bedding and furniture need to be completely decontaminated, while medicines like permethrin are not the easiest to use. David Cox, WIRED, 17 Jan. 2024 Repeat the cleaning process as needed, and the permethrin treatment one week later if your doctor recommends it. Christin Perry, Parents, 10 Aug. 2023 However, permethrin can be dangerous if applied directly to the skin, so be careful not to spray yourself. Steven Rowe, Health, 28 Aug. 2023 For longer lasting repellents to apply to your clothes, tent, and gear, products with permethrin can be very effective. Steven Rowe, Health, 28 Aug. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'permethrin.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


per- + methyl + pyrethrin

First Known Use

1975, in the meaning defined above

Time Traveler
The first known use of permethrin was in 1975

Dictionary Entries Near permethrin

Cite this Entry

“Permethrin.” Dictionary, Merriam-Webster, Accessed 17 Jun. 2024.

Medical Definition


per·​meth·​rin pər-ˈmeth-rən How to pronounce permethrin (audio)
: a synthetic pyrethroid pesticide C21H20Cl2O3 used especially against insects, ticks, and mites

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