ˈkɒn.tɹəˌsɛp.tɪv hɪtʃ ɪnˈkʌm.bɹənts ˌɪntəɹˈfiɹɨns pɹɪˈvɛntətɪv pɹɪˈvɛntətɪv pɹɪˈvɛntɪv pɹɪˈvɛntɪv pɹɒfəˈlæktɪk pɹɒfəˈlæktɪk preventing or contributing to the prevention of disease preventive medicine vaccines are prophylactic a prophylactic drug tending to prevent or hinder an agent or device intended to prevent conception any obstruction that impedes or is burdensome remedy that prevents or slows the course of an illness or disease the doctor recommended several preventatives