arrow slit; gun loop; gun port
Technical term for a narrow vertical opening in a fortification wall through which archers or gunners could fire. Used in historical and military contexts.
The castle walls were equipped with many arrow slits.
Aim at the enemy through this gun loop.
Compound of 射撃 (shooting) and 孔 (hole, opening). The exact historical derivation is uncertain, but the term is a straightforward technical compound.