Semi-automatic firearm

weapon that performs all steps necessary to prepare the weapon to fire again after firing, capable of firing only once with each activation of the trigger

A semi-automatic, or self-loading firearm is a gun that requires only a trigger pull for each round that is fired, unlike a single-action revolver, a pump-action firearm, a bolt-action firearm, or a lever-action firearm, which require the shooter to manually chamber each successive round. Also, unlike a double-action revolver, power from one shot is used load the next, instead of using power from pulling the trigger.

The M1 Garand. the first semi-automatic rifle to be generally issued to the infantry in any nation.
Remington 1100 Tactical Shotgun in 12 gauge - an example of a semi-automatic shotgun
Walther P99, a semi-automatic pistol from the late 1990s