forepass
/ˈfɔɪpæs/Definitions
1. noun
A passage or opening through a defensive wall or other fortification, especially one made in the side of a hill or mountain.
“The besieging army found a hidden forepass in the enemy’s defenses.”
2. verb
To pass through or make a passage through something, especially a defensive wall or other fortification.
“The soldiers forepassed the enemy’s defenses and reached the other side.”