pyrethrum

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

Definition of pyrethrum

1 : any of several chrysanthemums with finely divided often aromatic leaves including ornamentals as well as important sources of insecticides
2 : an insecticide made from the dried heads of any of several Old World chrysanthemums (especially Chrysanthemum cinerariaefolium)

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Origin and Etymology of pyrethrum

Latin, pellitory, from Greek pyrethron, from pyr fire


Medical Dictionary

pyrethrum

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

medical Definition of pyrethrum

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