Source : WordNet®

ward off
     v 1: prevent the occurrence of; prevent from happening; "Let's
          avoid a confrontation"; "head off a confrontation";
          "avert a strike" [syn: {debar}, {obviate}, {deflect}, {avert},
           {head off}, {stave off}, {fend off}, {avoid}]
     2: avert, turn away, or repel; "Ward off danger"