- A firearm with an automatic loading mechanism. A firearm that automatically loads the next cartridge to be fired into the chamber either upon the pull of the trigger in an open bolt design or upon the firing of the previous round in a close bolt design. Over time this term has been shortened to just "auto" and sometimes "automatic" thus creating confusion between a full-auto firearm and a semi-automatic firearm. An autoloader or auto-loader is a mechanical aid or replacement for the personnel that load ordnance into crew-served weapons, such as tanks and artillery. The term is generally only applied to larger weapons that would otherwisehave a dedicated person or persons loading them. Semi-automatic firearms are sometimes informally called "auto-loaders". However, this is a derivation of the term "auto-loading" rather than a physical "autoloader", as discussed here.
- An autoloader, as its name suggests, extracts a shell and propellant charge from the ammunition storage rack/compartment and loads it into a magazine, if the gun has one, or directly into the chamber of the gun if it does not. It can and often does replace a human loader.