Definition of pyrethrin
: either of two oily liquid esters C21H28O3 and C22H28O5 having insecticidal properties and occurring especially in the flowers of pyrethrum
Recent Examples of pyrethrin from the Web
The Extension recommends using a fast-acting aerosol insecticide containing pyrethrins if fire ants are detected among flood debris, though these insecticides can be toxic to aquatic organisms, so caution is recommended.
Pyrethrins and pyrethroids also work by interfering with sodium pores.
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Origin and Etymology of pyrethrin
International Scientific Vocabulary, from Latin pyrethrum
First Known Use: 1882See Words from the same year
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Britannica.com: Encyclopedia article about pyrethrin
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