@sidekickmatt: I decided to

A clean bill of health Origin: Ships had to have a “clean bill of health” from port authorities, certifying no contagious disease on board. Above board Origin: Goods kept “above board” (on deck) were not being smuggled. All hands on deck Origin: A call for all crew members to come to the deck and be ready for action. Batten down the hatches Origin: Securing the ship’s hatches with wooden battens before rough seas. Between the devil and the deep blue sea Origin: “The devil” was a seam in the hull of a wooden ship. Working on it meant being close to falling into the sea. By and large Origin: A sailing term describing a ship that sails well in both favorable ("by") and unfavorable ("large") winds. Close quarters Origin: Originally a term for a barricade used in shipboard fighting, now used to mean confined space. Cut and run Origin: To cut the anchor line and make a quick escape. Feeling blue Origin: A ship would fly blue flags and have a blue band painted along her hull when a captain or officer died. Hand over fist Origin: Refers to pulling on a rope quickly and efficiently, now means making rapid progress (often with money). Hard and fast Origin: A ship that was beached or stuck was “hard and fast.” Now means fixed or unchangeable. High and dry Origin: A ship stranded out of the water, now means abandoned or in a helpless situation. Know the ropes Origin: Sailors had to learn the rigging (ropes) of a ship; now means someone is experienced. Loose cannon Origin: An unsecured cannon on a ship could cause massive damage. Now refers to an unpredictable person. No room to swing a cat Origin: Refers to the cat-o’-nine-tails used for punishment—tight ship quarters made it hard to use. Over a barrel Origin: A drowning sailor might be placed over a barrel to expel water from their lungs. Later used for flogging too. Pipe down Origin: The boatswain’s pipe signaled the end of the day—crew had to be quiet. Shipshape Origin: Ships had to be kept orderly and tidy; now used to describe something neat and in good condition. Show one’s true colors Origin: Warships would sometimes hide their flags until battle. Showing true colors revealed true intent. Three sheets to the wind Origin: Refers to lines (sheets) that control sails—if loose, the ship would reel like a drunk person