Natural insecticide made from the blossoms of various chrysanthemums.
Merriam-Webster Online Dictionary
pyrethrum (noun)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
Chrysanthemum cinerariifolium, Chrysanthemum coccineum, Tanacetum cinerariifolium, Tanacetum coccineum, Dalmatian chrysanthemum
