1.NounAn organophosphate larvicide used especially to treat water infested with disease-carrying fleas. [O,O,O′,O′-tetramethyl O,O′-sulfanediylbis(1,4-phenylene) diphosphorothioate].
"Temefos is an organophosphorus insecticide used to control mosquito, midge, and black-fly larvae in lakes, ponds, and wetland habitats."