请输入您要查询的英文单词:

 

单词 pyrethrin
释义

Definition of pyrethrin in English:

pyrethrin

noun pʌɪˈriːθrɪn
Chemistry
  • Any of a group of insecticidal compounds present in pyrethrum flowers.

    pyrethrins can cause allergic reactions
    mass noun it contains natural pyrethrin
    Example sentencesExamples
    • Many of these sprays contain one or more of a group of insecticidal compounds known as pyrethrins.
    • These synthetic chemicals mimic the action of natural pyrethrins derived from chrysanthemum flowers.
    • If the infestation is severe, topically administered permethrin, pyrethrin, or malathion also may help.
    • Citrus-oil products, pyrethrin products, as well as those with pyrethrins and diatomaceous earth, may be effective.
    • If you absolutely have to, you can spray with an insecticidal soap or insecticide that contains pyrethrins.

Origin

1920s: from pyrethrum + -in1.

 
 

Definition of pyrethrin in US English:

pyrethrin

noun
Chemistry
  • Any of a group of insecticidal compounds present in pyrethrum flowers.

    pyrethrins can cause allergic reactions
    mass noun it contains natural pyrethrin
    Example sentencesExamples
    • These synthetic chemicals mimic the action of natural pyrethrins derived from chrysanthemum flowers.
    • If the infestation is severe, topically administered permethrin, pyrethrin, or malathion also may help.
    • If you absolutely have to, you can spray with an insecticidal soap or insecticide that contains pyrethrins.
    • Citrus-oil products, pyrethrin products, as well as those with pyrethrins and diatomaceous earth, may be effective.
    • Many of these sprays contain one or more of a group of insecticidal compounds known as pyrethrins.

Origin

1920s: from pyrethrum + -in.

 
 
随便看

 

英语词典包含464360条英英释义在线翻译词条,基本涵盖了全部常用单词的英英翻译及用法,是英语学习的有利工具。

 

Copyright © 2004-2022 Newdu.com All Rights Reserved
更新时间:2024/12/23 22:57:48