pyrethroid: Meaning and Definition of

py•re•throid

Pronunciation: (pī-rē'throid, -reth'roid), [key]
— n. Chem.
  1. any of several synthetic compounds that are similar to but more persistent than natural pyrethrins.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.