pyrethrum(redirected from pyrethrums)
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The root of Anacyclus pyrethrum (family Compositae), a shrub native to Morocco; has been used as a sialogogue; its flowers are a source of pyrethrins.
[G. pyrethron, feverfew, fr. pyr, fire, from the hot-tasting root]
pyrethruman INSECTICIDE prepared from the dried flowers of the chrysanthemum plant, the active ingredient being called pyrethrin.
flowers of the plants Chrysanthemum cinerariaefolium (syn. Pyrethrum cinerariaefolium) and C. coccineum (syn. C. roseum). Called also Dalmatian or Persian insect powder. The insecticidal agents are the pyrethrins.