a signal (often a sound) that shows that a place or situation is no longer dangerous
Example:
- The children hid in the basement until the all-clear sounded.
if a doctor gives somebody the all-clear, they tell the person that he/she does not have any health problems
Example:
- The building was given the all-clear following tests.
permission to do something
Example:
- The ship was given the all-clear to sail.