organophosphatePronunciation: /ɔːˌgənəʊˈfɒsfeɪt, ɔːˈganəʊˌfɒsfeɪt/Definition of organophosphate noun any organic compound whose molecule contains one or more phosphate ester groups, especially a pesticide of this kind. organophosphate in other Oxford dictionaries Definition of organophosphate in the US English dictionary