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py·re·thrum | \ pī-ˈrē-thrəm 
, -ˈre- \
, -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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More Definitions for pyrethrum
pyrethrum
nounpy·re·thrum | \ pī-ˈrē-thrəm , -ˈreth-rəm \
, -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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Time Traveler for pyrethrum
The first known use of pyrethrum was circa 1543
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