bel·lig·er·en·cy \-rənsē, -si\noun (-es) 1.: the state of being at war or in conflict; specifically: the status whereby a recognized military force is granted the protection of the international laws and usages of war (as those laid down by the Hague Convention in 1899) 2.: belligerence < over against this persistent belligerency of the German militarists stood the ideology of British pacifism — Hibbert Journal >