"The all clear" is an idiomatic expression used to signal that a potentially dangerous situation is over or that the area is safe. There are several synonyms for this term that can be used depending on the context. "Green light" is a phrase that can be used in a similar situation, indicating that it is safe to proceed. "Safe passage" is another term that can be used to indicate that it is safe to move forward or enter a particular area. "The coast is clear" is a more casual synonym that means the same thing. Other phrases that convey a similar meaning include "all good," "all systems go," and "situation resolved".