all clear

柯林斯词典

1. N-SING The all clear is a signal that a dangerous situation, for example, an air raid, has ended. 危险解除的信号['the' N]
The all clear was sounded about 10 minutes after the alert was given. 警报响起十分钟后，危险解除的信号就响了。
2. N-SING If someone in authority gives you the all clear, they give you permission to continue with a plan or activity, usually after a problem has been sorted out. 许可; 批准['the' N]
I was given the all clear by the doctor to resume playing. 医生批准我继续参加比赛了。