Taking the ship into shallow waters or out of the water altogether to scrape off barnacles, weed and all the other pesky stuff that likes to grow on the bottom of the hull. It Found on http://black-bart.co.uk/html/pirate_glossary.html
Careening a sailing vessel is the practice of beaching it at high tide. This is usually done in order to expose one side or another of the ship`s hull for maintenance and repairs below the water line when the tide goes out. This practice is also known as to `heaving down`. The process could be assisted by securing a top halyard to a fixed objec...... Found on http://en.wikipedia.org/wiki/Careening
Careening is a nautical term for heaving or bringing a ship to lie on one side for the purpose of caulking, repairing, cleansing, paying with pitch, or the like. Found on http://www.probertencyclopaedia.com/browse/RC.HTM