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pyrethrum

Syllabification: py·re·thrum
Pronunciation: /pīˈrēTHrəm, -ˈreTHrəm
 
/

Definition of pyrethrum in English:

noun

1An aromatic plant of the daisy family, typically having feathery foliage and brightly colored flowers.
  • Genus Tanacetum (formerly Chrysanthemum or Pyrethrum), family Compositae: several species, in particular T. coccineum, grown as an ornamental, and T. cinerariifolium, grown as a source of the insecticide pyrethrum
Example sentences
  • Not all herbs smell good - catmint, curry plant, pyrethrum, rue, santolina and tansy are all pretty pongy.
  • Some are derived from plants, such as pyrethrum and neem.
  • When I looked closely I could see the truck had a PyGanic label with the iconic pyrethrum flower on the side.
1.1An insecticide made from the dried flowers of the pyrethrum plant.
Example sentences
  • By the mid 1800s, the heads of chrysanthemum flowers were used to obtain pyrethrum, and rotenone was extracted from the derris plant.
  • Pesticides that are approved for organic farming include copper, sulfur, petroleum distillates, and pyrethrum.
  • Daisy plants were first used centuries ago as a lice remedy in the Middle East, and this led to the discovery of pyrethrum insecticides.

Origin

Middle English (denoting pellitory): from Latin, from Greek purethron 'feverfew'. The current senses (based on the former genus name) date from the late 19th century.

Words that rhyme with pyrethrum

maelstromcerebrum

Definition of pyrethrum in:

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