The REAL Pirates Dictionary

Addled  Mad, insane, or just stupid. An "addlepate" is a fool
Aft Short for "after." Toward the rear of the ship.
Ahoy  Hello!
Avast! Hey! Could also be used as "Stop that!" or "Who goes there?"
Begad! By God!
Belay Stop that. "Belay that talk!" would mean "Shut up!"
Bilge! Nonsense, or foolish talk.
The bilges of a ship are the lowest parts, inside the hull along the keel.
They fill with stinking bilgewater—or just "bilge."
Bilge-sucking A very uncomplimentary adjective.
Black Spot To "place the Black Spot" on another pirate is to sentence him to death, to warn him he is marked for death, or sometimes just to accuse him of a serious crime before other pirates.
Blaggard Blackguard. An insult.
Blimey! An exclamation of surprise.
Booty Loot. Bosun Boatswain, a petty officer.
Bucko Familiar term. "Me bucko" = "my friend."
Cap'n Short for "captain."
Cat o'nine tails A whip with many lashes, used for flogging. "A taste of the cat" might refer to a full flogging, or just a single blow to "smarten up" a recalcitrant hand.
Chantey A sailor's work song. Also spelled "shantey" or "shanty."
Corsair A more romantic term for pirate. But still a pirate.
Davy Jones' locker  The bottom of the sea.
Deadlights Eyes. "Use yer deadlights, matey!"
Dead men tell no tales  Standard pirate excuse for leaving no survivors.
Dog A mild insult, perhaps even a friendly one.
Doubloon A Spanish gold coin. At different times, it was worth either 4 or 16 silver pesos, or "pieces of eight." Fair winds! Goodbye, good luck!
Feed the fish What you do when you are thrown into the sea, dead or alive.
Gangway!  "Get out of my way!"
Godspeed! Goodbye, good luck!
Grub Food.
Fore, or forrard Toward the front end of the ship.
Flogging Punishment by caning, or by whipping with the cat.
Hands The crew of a ship; sailors.
Handsomely Quickly. "Handsomely now, men!" = "Hurry up!"
Jack Ketch The hangman. To dance with Jack Ketch is to hang.
Jollyboat A small but happy craft, perhaps even one which is a little dinghy.
Jolly Roger  The pirates' skull-and-crossbones flag. It was an invitation to surrender, with the implication that those who surrendered would be treated well.
A red flag indicated "no quarter."
Keelhaul Punishment by dragging under the ship, from one side to the other. The victim of a keelhauling would be half-drowned, or worse, and lacerated by the barnacles that grew beneath the ship.
Kiss the gunner's daughter A punishment: to be bent over one of the ship's guns and flogged.
Lad, lass, lassie A way to address someone younger than you.
Landlubber or just lubber  A non-sailor. 
Lights Lungs. A pirate might threaten to "have someone's lights and liver."
Line A rope in use as part of the ship's rigging, or as a towing line. When a rope is just coiled up on deck, not yet being used for anything, it's all right to call it a rope.
Lookout Someone posted to keep watch on the horizon for other ships or signs of land.
Maroon A  common punishment for violation of a pirate ship's articles, or offending her crew. The victim was left on a deserted coast (or, island) with few supplies. That way, no one could say that the unlucky pirate had actually been killed by his former brethren.
Me A piratical way to say "my."
Me hearties  Typical way for a pirate leader to address his crew.
Matey A piratical way to address someone in a cheerful, if not necessarily friendly, fashion.
No quarter! Surrender will not be accepted.
Piece of eight A Spanish silver coin worth one peso or 8 reales. It was sometimes literally cut into eight pieces, each worth one real.
Pillage To raid, rob, and sack a target ashore.
Pirate A seagoing robber and murderer. Contrast with privateer.
Poop deck The highest deck at the aft end of a large ship. Smaller ships don't have a poop; the highest part aft is the quarterdeck.
Poxy, poxed Diseased. Used as an insult.
Rope's end Another term for flogging. "Ye'll meet the rope's end for that, me bucko!"
Rum (noun) Traditional pirate drink.
Rum (adjective) Strange or odd. A "rum fellow" is a peculiar person, the sort who won't say "Arrrr!" on Talk Like A Pirate Day.
Sail ho!  "I see a ship!" The sail, of course, is the first part of a ship visible over the horizon.
Salt, old salt An experienced seaman.
Scurvy (1) A deficiency disease caused by lack of vitamin C, often afflicting sailors;
(2) A derogatory adjective for an epithet, as in "Ye scurvy dogs!"

Sea dog An experienced seaman.
Shanty Another spelling for "chantey" - a sea song.
Shark bait (1) Your foes, who are about to feed the fish (q.v.).
(2) A worthless or lazy sailor; a lubber who is no use aboard ship.
Shiver me timbers!  An expression of surprise or strong emotion.
Sink me! An expression of surprise.
Smartly Quickly. "Smartly there, men!" = "Hurry up!"
Splice the mainbrace To have a drink. Or, perhaps, several drinks.
Spyglass A telescope.
Starboard The right side of the ship when you are facing toward her prow.
Sutler A merchant in port, selling what a ship needed for supplies and repairs.
Swab (noun) A disrespectful term for a seaman. "Man that gun, ye cowardly swabs!"
Swab (verb) To clean something. "Swabbing the decks" would be a mild penalty for a disobedient pirate.
Swag Loot.
Wench An individual of the female persuasion. "Saucy" is a good adjective to add to this, and if ye can get away with "Me proud beauty,” more power to ye!
Yo-ho-ho A very piratical thing to say, whether it actually means anything or not.