noun
old enemy; former foe
Refers to a person, group, or nation that was once an enemy, often in a historical or narrative context. Can carry a nuance of past conflict now resolved or remembered.
戦後、旧敵国との関係改善が進んだ。
After the war, relations with former enemy nations improved.
彼はかつての旧敵と握手を交わした。
He shook hands with his old enemy from the past.