pyrethrin

noun

py·​re·​thrin pī-ˈrē-thrən How to pronounce pyrethrin (audio) -ˈre- How to pronounce pyrethrin (audio)
: either of two oily liquid esters C21H28O3 and C22H28O5 having insecticidal properties and occurring especially in the flowers of pyrethrum

Examples of pyrethrin in a Sentence

Recent Examples on the Web Similar to permethrin lotion, pyrethrins don't kill unhatched eggs, so a second treatment is usually recommended 9 days after the first. USA TODAY, 16 Mar. 2024 Use them sparingly, and only if necessary; most feature pyrethrins or their synthetic version, pyrethroids. Brett Martin, Popular Mechanics, 17 May 2023 This seasonal favorite contains many different toxins, including pyrethrins, which can cause GI upset, drooling, vomiting, and diarrhea. Arricca Elin Sansone, House Beautiful, 22 Apr. 2023 There are many organic or natural remedies for mealy bugs and spider mites, including neem oil and pyrethrin, and one of the most effective ways to get rid of scale is to simply wipe your plants with a cotton ball or Q-tip full of rubbing alcohol, and then rub them off. Dean Kuipers, Outside Online, 15 Apr. 2022 Chang suggests applying permethrin 1 percent lotion or other pyrethrin-containing topical agents. Bill Sullivan, Discover Magazine, 5 June 2021 For aphids, hose off as many as possible and then use either Mosquito Bits (a Baccillus product that nurseries sell) or spray plants with any product containing pyrethrin. Earl Nickel, San Francisco Chronicle, 1 Apr. 2022 The team also used chemical analysis to determine how two of pyrethrum’s molecular components—EBF and pyrethrin—elicit the repellent response. Rachel Nuwer, Scientific American, 19 July 2021 Adults can be controlled with malathion, carbaryl (Sevin) and pyrethrin. From Usa Today Network and Wire Reports, USA TODAY, 29 June 2021

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

Word History

Etymology

International Scientific Vocabulary, from Latin pyrethrum

First Known Use

1882, in the meaning defined above

Time Traveler
The first known use of pyrethrin was in 1882

Dictionary Entries Near pyrethrin

Cite this Entry

“Pyrethrin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pyrethrin. Accessed 28 Mar. 2024.

Medical Definition

pyrethrin

noun
py·​re·​thrin pī-ˈrē-thrən How to pronounce pyrethrin (audio) -ˈreth-rən How to pronounce pyrethrin (audio)
: either of two oily liquid esters C21H28O3 and C22H28O5 that have insecticidal properties and are the active components of pyrethrum

More from Merriam-Webster on pyrethrin

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