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pyrethrum

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noun py·re·thrum \pī-ˈrē-thrəm, -ˈre-\

Definition of pyrethrum

  1. 1 :  any of several chrysanthemums with finely divided often aromatic leaves including ornamentals as well as important sources of insecticides

  2. 2 :  an insecticide made from the dried heads of any of several Old World chrysanthemums (especially Chrysanthemum cinerariaefolium)



Origin and Etymology of pyrethrum

Latin, pellitory, from Greek pyrethron, from pyr fire


First Known Use: circa 1543


Medical Dictionary

pyrethrum

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noun py·re·thrum \pī-ˈrē-thrəm, -ˈreth-rəm\

Medical Definition of pyrethrum

  1. 1:  any of several chrysanthemums with finely divided often aromatic leaves including ornamentals as well as important sources of insecticides

  2. 2:  an insecticide consisting of or derived from the dried heads of any of several Old World chrysanthemums (genus Chrysanthemum of the family Compositae)




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