chlordanePronunciation: /ˈklɔːdeɪn/Definition of chlordane noun [mass noun] a synthetic viscous toxic compound used as an insecticide. A chlorinated derivative of indene; chemical formula: C10H6Cl8 Origin: 1940s: from chlor- (representing chlorine) + (in)dene + -ane2chlordane in other Oxford dictionaries Definition of chlordane in the US English dictionary