En barbette, In barbette, said of guns when they are elevated so as to fire over the top of a parapet, and not through embrasures. -- Barbette gun, or Barbette battery, a single gun, or a number of guns, mounted in barbette, or partially protected by a parapet or turret. -- Barbette carriage, a gun carriage which elevates guns sufficiently to be in barbette. [See Illust. of Casemate.]

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OXFORD DICTIONARY

barbette, n. a platform in a fort or ship from which guns can be fired over a parapet etc. without an embrasure.

Etymology

F, dimin. of barbe beard

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