1. a covered passage or gallery in a fortification, typically connecting two parts of a fort or allowing protected movement across a ditch
Usage: military/fortification term; also spelled 'caponnière'

Examples

• The caponier allowed soldiers to move safely between the two bastions without exposure to enemy fire.
• Engineers designed the caponier to span the moat and provide protected access to the outer defenses.
• The fort's caponier was reinforced with stone and earth to withstand artillery bombardment.
• During the siege, defenders used the caponier to reinforce weakened sections of the fortification.