automatic
/ˌɔdəˈmædɪk/
adjective
(of a device or process) working by itself with little or no direct human control.
an automatic kettle that switches itself off when it boils
mechanized,mechanical,automated,push-button,preprogrammed,computerized,electronic,robotic,unmanned
noun
A gun that continues firing until the ammunition is exhausted or the pressure on the trigger is released.
the rapid fire of automatics