noun, noun or participle which takes 'suru'
outside a castle; outside the castle
Refers to the area outside the walls or grounds of a castle. Can be used as a noun or with する to mean 'to go outside the castle'.
敵軍は城外に陣を張った。
The enemy army set up camp outside the castle.
城主はめったに城外に出なかった。
The lord of the castle rarely went outside the castle.