gun turret

A gun turret is a device that protects the crew or mechanism of a projectile firing weapon and at the same time lets the weapon be aimed and fired in many directions.A turret is usually a rotating weapon platform. This can be mounted on a fortified building or structure such as an anti-naval land battery, or on an armoured fighting vehicle, a naval ship, or a military aircraft.Turrets may be armed with one or more machine guns, automatic cannon, large-calibre guns, or missile launchers. It may be manned or remotely controlled, and is often armoured. A small turret, or sub-turret on a larger one, is called a cupola. The term cupola also describes rotating turrets that carry no weapons but instead sighting devices, as in the case of tank commanders.
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Noun
1. a self-contained weapons platform housing guns and capable of rotation
(synonym) gun enclosure, turret
(hypernym) platform, weapons platform
(part-holonym) tank, army tank, armored combat vehicle, armoured combat vehicle