Battlement
WordNet
noun
(1) A rampart built around the top of a castle with regular gaps for firing arrows or guns
WiktionaryText
Noun
- 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.
- Any high wall for defense.