Where did the phrase "The coast is clear" come from?

Question

Where did the phrase "The coast is clear" come from?

Answer 1

the coast is clear means 'everything is all good'

when the coast is clear - the right conditions are present. no fog or mist therefore ships are ready to set sail!

Answer 2

A nautical expression meaning:There is no fog or other obstacle to departure from a harbor or dockage.

Origin;

The phrase first appears in print in 1531 where it describes a vessel which had safely cleared the coast, then later Shakespeare used it in 'Henry VI' as a reference to visibility. "Salty Dog Talk: The Nautical Origins of Everyday Expressions" by Bill Beavis and Richard G. McCloskey

Answer 3

the harbor is clear of enemies