A white odorless crystalline solid, C10 Cl12 , formerly used as an insecticide against ants and as a fire retardant. It was banned in the United States in 1978 because of its effects on the environment and possibly on human health.
An insecticide consisting of a chlorinated hydrocarbon, C10Cl12, usually mixed with a bait and used esp. against fire ants.
Origin of mirex
Perhaps (pis)mir(e) ex(terminate)