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pyrethrin

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pyrethrin

Main Entry:: py·re·thrin
Pronunciation:: \pī-ˈrē-thrən, -ˈre-\
Function:: noun
Etymology:: International Scientific Vocabulary, from Latin pyrethrum
Date:: 1871

: either of two oily liquid esters C₂₁H₂₈O₃ and C₂₂H₂₈O₅ having insecticidal properties and occurring especially in the flowers of pyrethrum

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