pyrethrin

noun
py·​re·​thrin | \ pī-ˈrē-thrən How to pronounce pyrethrin (audio) , -ˈre- How to pronounce pyrethrin (audio) \

Definition of pyrethrin

: 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 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 mosquito repellents rely on a pyrethrin as the active ingredient. Outdoor Life Staff, Outdoor Life, 11 Jan. 2021 People who have known sensitivities to pyrethrin can reduce potential for exposure by staying indoors during treatment. Kristen Jordan Shamus, Detroit Free Press, 17 Sep. 2020 Acephate and pyrethrins are high toxicity to bees and horticultural oils are moderately toxic to bees. oregonlive, 20 Oct. 2019 For pubic lice, lice-killing lotions that contain active ingredients called permethrin, pyrethrins, or piperonyl butoxide, can be applied to the area. Sarah Bradley, Health.com, 24 Oct. 2019 Aphids, though more nuisance than major threat, can be treated with one of many sprays that have pyrethrin as a active ingredient. Earl Nickel, SFChronicle.com, 20 Sep. 2019 See More

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

First Known Use of pyrethrin

1882, in the meaning defined above

History and Etymology for pyrethrin

International Scientific Vocabulary, from Latin pyrethrum

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Time Traveler for pyrethrin

Time Traveler

The first known use of pyrethrin was in 1882

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Dictionary Entries Near pyrethrin

pyret-

pyrethrin

pyrethroid

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Cite this Entry

“Pyrethrin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pyrethrin. Accessed 3 Jul. 2022.

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More Definitions for pyrethrin

pyrethrin

noun
py·​re·​thrin | \ pī-ˈrē-thrən How to pronounce pyrethrin (audio) , -ˈreth-rən How to pronounce pyrethrin (audio) \

Medical Definition of pyrethrin

: 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

Britannica.com: Encyclopedia article about pyrethrin

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