any instrument or object used with the intent to threaten, injure, or kill. Examples include guns, knives, razor blades or other sharp-edged objects, ice picks, other pointed objects (including pens, pencils), baseball bats, frying pans, sticks, rocks, and bottles.
A tool designed for a human being to enable her to protect herself, or to commit agression against other people, or (sometimes) to take game. Not all firearms are weapons. Many firearms are designed and used only for target shooting or for competitions involving speed and accuracy.