Entry 1 sense Webster, 1913 Drastic /drăs'-tĭk/ · Dras·tic · IPA /ˈdrɑːstɪk/ 01 a. Acting rapidly and violently; efficacious; powerful; -- opposed to bland; as, drastic purgatives. 1. Acting rapidly and violently; efficacious; powerful; -- opposed to bland; as, drastic purgatives.(Med.)