noun, noun or participle which takes 'suru'
breaking a siege; lifting a siege
Military term for relieving a besieged force or breaking through an encirclement. Can be used as a noun or with する.
援軍が到着し、解囲に成功した。
Reinforcements arrived and succeeded in breaking the siege.
城を解囲するために、別動
To lift the siege of the castle, a detached force attacked from the rear.