GNU Collaborative International Dictionary of English

Found one definition

1.       
   firepower n.
   1. (military) The relative capacity for delivering weapons fire on a target; as, “the battleship has more firepower than a cruiser”.
   
   [WordNet 1.5]
   
   
   2. [figurative] A measure of the resources available to a group which allows them to achieve their objectives; capacity for action.
   
   [PJC]