expression, godan verb (-ru)
betray one's country; sell out one's country
Fixed expression meaning to betray one's country to an enemy, often implying treason or selling national interests.
スパイは国を売って敵に情報を渡した。
The spy betrayed his country and handed information to the enemy.
彼は金のために国を売った
He was accused of selling out his country for money.