An imprecise term used by military strategists and tacticians to express the relative capacity of a military force to shoot at and inflict damage upon an enemy force.
More contemporarily, the term finds frequent use in gun control debates to suggest that a specific model of firearm enables the user to shoot more: more rapidly, more rounds, more accurately, more potent caliber, or any combination of these.
The term tends to be used similarly in fiction.
Honestly, the term doesn’t mean anything, so I suppose it is fair to use it to mean anything you want.