rec·ti·fy / ˈrektəˌfī/ • v. (-fies, -fied) [tr.] 1. put (something) right; correct: mistakes made now cannot be rectified later efforts to rectify the situation. ∎ [usu. as adj.] (rectified) purify or refine (a substance), esp. by repeated distillation: add 10 cc of rectified alcohol.2. convert (alternating current) to direct current: [as adj.] (rectified) rectified AC power systems. 3. find a straight line equal in length to (a curve).DERIVATIVES: rec·ti·fi·a·ble adj.rec·ti·fi·ca·tion / ˌrektəfiˈkāshən/ n.