Parapet.

Fortification, the shot-proof covering of a mass of earth on the exterior edge of the ramparts. The openings cut through the parapets to permit guns to fire in the required direction are called embrasures: about 18 feet is allowed from one embrasure to another, and the solid intervening part is called the merlon. An indented parapet is a battlement. (Italian, parapetto, breastwork.)