Source : WordNet®

rallying cry
     n 1: a slogan used to rally support for a cause; "a cry to arms";
          "our watchword will be `democracy'" [syn: {war cry}, {battle
          cry}, {cry}, {watchword}]
     2: a yell intended to rally a group of soldiers in battle [syn:
         {war cry}, {war whoop}, {battle cry}]