What does "barbette" mean?

Barbette: A mound of earth or a platform in a fortification, on which guns are mounted to fire over the parapet. 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.]