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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 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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