In fortification, a work raised considerably higher than its neighbours, but generally of similar plan. Its object is to afford a plunging fire, especially into the near approaches of a besieger, and to shelter adjacent faces from enfilade. Its most frequent position in fortresses is at the salient of the ravelin, or within the bastion; and in siege-works in the advanced trenches, for the purpose of enabling the musketry of the attack to drive the defenders out of the covered way.