(military) A massive and heavy mobile artillery gun, built, transported by, and fired from a specially designed rail car.

An electroshock gun; a taser; a stun gun. / A gun with electrically powered components, such as the reloader or barrel rotator.

(physics) Any device that produces a stream of electrons, especially a narrow stream that is focused onto a phosphor screen.

plural of pop gun

A hand-held (or mounted) device that emits a radar beam and uses the Doppler effect to measure the velocity of moving objects (especially traffic)

(video games) A device resembling a gun that allows the player of a video game to target a point on the screen.

plural of laser gun

plural of light gun

plural of chain gun

A machine gun or autocannon that uses an external power source via a continuous loop of chain.