An opening in the wall of a fortress through which the guns are levelled; a narrow loophole through which arrows and other missiles may be shot.
A tower at the entrance to a castle or fortified town
A fortress at the end of a bridge.
A temporary wooden tower built for defensive purposes.
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.