1) a shaped piece of lead (to be) fired from a rifle or a revolver (bullet)

2) a large, heavy gun, especially the old kind that fired a solid ball of metal (cannon)

3) (to use) a spear on a rope, thrown by hand or fired from a gun, for catching (large sea-animals) (harpoon)

4) (of a shot) fired at very close range (point-blank)

5) a kind of gun with a long barrel, (to be) fired from the shoulder; to search (something) thoroughly in order to steal (rifle)