Wiktionary
ethion
n. (context organic compound English) An organophosphate insecticide, [dethoxyphosphinothioylthio)methylthio]-diethoxy-thioxophosphorane, that is known to neutralise the neural enzyme acetylcholinesterase.
Wikipedia
Ethion
Ethion (CHOPS) is an organophosphate insecticide. Ethion is known to affect a neural enzyme called acetylcholinesterase and prevent it from working.