pyrethrum

[ pahy-ree-thruhm, -reth-ruhm ]

noun

1. any of several chrysanthemums, as Chrysanthemum coccineum, having finely divided leaves and showy red, pink, lilac, or white flowers, cultivated as an ornamental.
2. any of several chrysanthemums, as C. cinerariifolium, or C. coccineum, cultivated as a source of insecticides.
3. Pharmacology. the dried flower heads of these plants, used chiefly as an insecticide and sometimes in medicine for certain skin disorders.

pyrethrum

/ paɪˈriːθrəm /

noun

1. any of several cultivated Eurasian chrysanthemums, such as Chrysanthemum coccineum and C. roseum, with white, pink, red, or purple flowers
2. any insecticide prepared from the dried flowers of any of these plants, esp C. roseum

Word History and Origins

Origin of pyrethrum¹

First recorded in 1555–65; from Latin, from Greek pýrethron, the name of the flower, akin to pyretós “fever”

Word History and Origins

Origin of pyrethrum¹

C16: via Latin from Greek purethron feverfew, probably from puretos fever; see pyretic

Example Sentences

The team also used chemical analysis to determine how two of pyrethrum’s molecular components—EBF and pyrethrin—elicit the repellent response.

From Scientific American

The Documentary category was won by Vito Fusco, of Italy, for his series on Kenya's pyrethrum flowers, which are used as a natural insecticide.

From BBC

As we head north, Rwanda’s pristine landscape morphs into an undulating canvas of forest, farms and fields of pyrethrum flowers, a cash crop sold as a natural insecticide.

From Washington Post

Meanwhile men in Serbia were known to consume a “happy porridge” aphrodisiac made from hashish, almond butter, flower petals and leaves, spices, and Anacyclus pyrethrum root.

From Salon

Seventy-two percent of OTC lice products sold in the United States contain either permethrin or pyrethrum.

From US News