Barbette

Barbette is a word with several related but distinct meanings. In recent naval usage, a 'barbette' is a protective circular armour support for a heavy gun turret. This evolved from earlier forms of gun protection that eventually led to the predreadnought. The name ultimately comes from fortification, originally meaning a raised platform or mound, seen in the French phrase en barbette, which refers to the practice of firing a cannon over a parapet rather than through an embrasure in the fortification. The former gives better angles of fire but less protection than the latter. The disappearing gun was a variation on the barbette gun; it consisted of a heavy gun on a carriage that would retract behind a parapet or into a gunpit for reloading. They were primarily used in coastal defences, but saw some use in a handful of warships, and some inland fortifications. The term is also used for certain aircraft gun mounts.

Shipboard barbettes were primarily used in armoured warships starting in the 1860s during a period of intense experimentation with other mounting systems for heavy guns at sea; alternatives included the heavily armored gun turret and an armored, fixed central gun battery. By the late 1880s, all three systems were replaced with a hybrid barbette-turret system that combined the benefits of both types. The heavily armored tube that supported the new gun mount was referred to as a barbette.