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

They’re made with a patented Insect Shield technology in which permethrin is blended into the fibers. — Olivia Young, Travel + Leisure, 7 Aug. 2026

Experts also recommend applying insect repellent, such as permethrin, to clothing and outdoor gear, not directly on the skin. — Teresa Mull, FOXNews.com, 1 Aug. 2026

Acaricides, like permethrin, are meant for gear and clothing. — Rae Ford, Martha Stewart, 18 July 2026

Yard sprays, such as bifenthrin and permethrin, can help to reduce tick populations in your yard, but it’s recommended to hire a licensed professional to do this. — Amanda Roome, The Conversation, 16 July 2026

Word History

Etymology

per- + methyl + pyrethrin

First Known Use

1975, in the meaning defined above

Medical Definition

permethrin

noun

per·​meth·​rin pər-ˈmeth-rən 

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