pyrethrin

[ pahy-ree-thrin, -reth-rin ]

nounChemistry.
  1. Also called pyrethrin I. a viscous, water-insoluble liquid, C21H28O3, extracted from pyrethrum flowers, used as an insecticide.

  2. Also called pyrethrin II. a like compound, C22H28O5, obtained and used similarly.

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Origin of pyrethrin

1
First recorded in 1830–40; pyrethr(um) + -in2

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British Dictionary definitions for pyrethrin

pyrethrin

/ (paɪˈriːθrɪn) /


noun
  1. Also called: pyrethrin I an oily water-insoluble compound used as an insecticide. Formula: C 21 H 28 O 3

  2. Also called: pyrethrin II a compound of similar chemical structure and action, also found in pyrethrum. Formula: C 22 H 28 O 5

Origin of pyrethrin

1
C19: from pyrethrum + -in

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