anticonvulsant Syllabification: (an·ti·con·vul·sant)Pronunciation: /ˌantēkənˈvəlsənt, ˌantī-/Definition of anticonvulsant adjective (chiefly of a drug) used to prevent or reduce the severity of epileptic fits or other convulsions. noun an anticonvulsant drug. anticonvulsant in other Oxford dictionaries Definition of anticonvulsant in the British & World English dictionary