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to attack; to destroy; to defeat; to conquer; to avenge
武士は敵を討つために故郷を出発した。
We departed to defeat the enemy.
彼は父の仇を討つことを生涯誓った。
He swore a lifelong oath to avenge his father.
彼らの軍隊が反乱軍を討った。
Their army defeated the rebel forces.