from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. Any of several Old World plants of the genus Chrysanthemum, such as C. coccineum, cultivated for their showy flower heads.
  • n. An insecticide made from the dried flower heads of Chrysanthemum cinerariifolium or C. coccineum.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. Any of several perennial African plants of the genus Chrysanthemum, especially Chrysanthemum cinerariaefolium
  • n. Any of several insecticides obtained from these plants; pyrethrin

from The Century Dictionary and Cyclopedia

  • n. A plant of the genus Pyrethrum; feverfew.
  • n. [capitalized] A former genus of composite plants of the tribe Anthemideæ, now included as part of the section Pyrethra in the genus Chrysanthemum, from which it was distinguished by achenes nearly equally from five- to ten-ribbed and crowned with a pappus, characters now known to vary in the same species.
  • n. A powdered preparation of pyrethrum, used as an insectifuge. Also called pyrethrum-powder. See insect-powder and buhach.
  • n. In pharmacy, the Anacyclus Pyrethrum, or pellitory-of-Spain.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. made of dried flower heads of pyrethrum plants
  • n. white-flowered pyrethrum of Balkan area whose pinnate leaves are white and silky-hairy below; source of an insecticide; sometimes placed in genus Chrysanthemum
  • n. used in former classifications for plants later placed in genus Chrysanthemum and now often included in genus Tanacetum
  • n. spring-flowering garden perennial of Asiatic origin having finely divided aromatic leaves and white to pink-purple flowers; source of an insecticide; sometimes placed in genus Chrysanthemum


Latin, pellitory, from Greek purethron, feverfew, from pūr, fire (from its warming effect); see pyretic.
(American Heritage® Dictionary of the English Language, Fourth Edition)



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  • Yeah, I'm just quoting the book.

    October 6, 2008

  • Mosquitoes aren't attracted to light.

    October 6, 2008

  • An insecticide that doesn't kill bats.

    October 6, 2008

  • "Pyrethrum, an insect powder, was burned inside the room, and a light was held in the corner to attract wayward mosquitoes and stun them."
    —Molly Caldwell Crosby, The American Plague (New York: Berkeley Books, 2006), 204

    October 6, 2008