In fortification: an indented parapet, formed by a series of rising members called cops or merlons, separated by openings called crenelles or embrasures, the soldier sheltering himself behind the merlon while he fires through the embrasure or through a loophole in the battlement.
The towering roof of heaven.
Any high wall for defense.
A pattern along the top of a parapet (fortified wall), most often in the form of multiple, regular, rectangular spaces in the top of the wall, through which arrows or other weaponry may be shot, especially as used in medieval European architecture.
The act of crenellating; adding a top row that looks like the top of a medieval castle.
Any of a series of notches with fancied resemblance to such battlements, as for example around the bezel of a flashlight.