pyrethroid
noun
py·re·throid
pī-ˈrē-ˌthrȯid 
-ˈre-
-ˈre-
: any of various synthetic compounds that are related to the pyrethrins and resemble them in insecticidal properties
pyrethroid
adjective
Examples of pyrethroid in a Sentence
Recent Examples on the Web
Look for a product labeled for caterpillar management, including pyrethroids such as permethrin or bifenthrin.
—
Arricca Elin Sansone, Southern Living, 21 June 2025
One of the synthetic pyrethroids could also help control the young lubber grasshoppers.
—Tom MacCubbin, The Orlando Sentinel, 5 Apr. 2025
Iowa State said spraying pyrethroid insecticides such as Permethrin or Esfenvalerate on the outside of buildings when the beetles appear may help prevent pest entry, especially for large infestations.
—Jalen Williams, Detroit Free Press, 31 Oct. 2024
As another preemptive step, which may be easier than physically sealing gaps around your house, spray pyrethroid insecticides around any openings into the home.
—Maia Pandey, Journal Sentinel, 28 Oct. 2024
See All Example Sentences for pyrethroid
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Arricca Elin Sansone, Southern Living, 21 June 2025
One of the synthetic pyrethroids could also help control the young lubber grasshoppers.
—Tom MacCubbin, The Orlando Sentinel, 5 Apr. 2025
Iowa State said spraying pyrethroid insecticides such as Permethrin or Esfenvalerate on the outside of buildings when the beetles appear may help prevent pest entry, especially for large infestations.
—Jalen Williams, Detroit Free Press, 31 Oct. 2024
As another preemptive step, which may be easier than physically sealing gaps around your house, spray pyrethroid insecticides around any openings into the home.
—Maia Pandey, Journal Sentinel, 28 Oct. 2024
See All Example Sentences for pyrethroid
Cite this Entry
“Pyrethroid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pyrethroid. Accessed 31 Oct. 2025.
Copy CitationMedical Definition
pyrethroid
noun
py·re·throid
pī-ˈrē-ˌthrȯid
-ˈreth-ˌrȯid
-ˈreth-ˌrȯid
: any of various synthetic compounds that are related to the pyrethrins and resemble them in insecticidal properties
pyrethroid
adjective
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