pyrethrum

noun

py·​re·​thrum pī-ˈrē-thrəm  -ˈre- 

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)

Examples of pyrethrum in a Sentence

Recent Examples on the Web

Having hit the global market it was abandoned during the 1980s due to the pyrethrum crisis but Fusco documents the journey of this flower and its market return under the Kenyan government in an ambitious attempt to help farmers meet the growing global demand for organic products. —Joanne Shurvell, Forbes, 15 Apr. 2021

In 1807, chemists isolated pyrethrum from an Armenian daisy. —Carl Zimmer, Discover Magazine, 4 May 2010

To observe pyrethrum’s effects, Dong and her colleagues attached tiny electrodes to hairs on mosquitoes’ antennae. —Rachel Nuwer, Scientific American, 19 July 2021

Do not use pyrethrum products for these or any other pests. —Howard Garrett, Dallas News, 26 July 2021

Lives can be spared by applying insect repellents, including a chrysanthemum flower extract called pyrethrum that humans have used for thousands of years. —Rachel Nuwer, Scientific American, 19 July 2021

During the 1980s, the pyrethrum crisis began, instigated by the chemical synthesis of pyrethroids that led to the manufacturing of cheaper but non-organic products. —Cecilia Rodriguez, Forbes, 4 Mar. 2021

The pyrethrum is known as the ‘flower of death’ – a nickname that neatly describes this delicate daisy imbued with murderous power. —Cecilia Rodriguez, Forbes, 4 Mar. 2021

The pyrethrum is cultivated mainly in the hills of Nakuru in Kenya and is the arch foe of the insect world. —Cecilia Rodriguez, Forbes, 4 Mar. 2021

Word History

Etymology

Latin, pellitory, from Greek pyrethron, from pyr fire

First Known Use

circa 1543, in the meaning defined at sense 1

Kids Definition

pyrethrum

noun

py·​re·​thrum pī-ˈrē-thrəm  -ˈreth-rəm 

1

: any of several chrysanthemums that have finely divided leaves and include ornamental plants as well as important sources of insecticides

2

: an insecticide consisting of the dried heads of some Old World pyrethrums

Medical Definition

pyrethrum

noun

py·​re·​thrum pī-ˈrē-thrəm  -ˈreth-rəm 

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)