Aaaarrrrgggghhhh! - disgust or frustration

Ahoy - hello

Ahoy Matey - hello friend!

Ahoy me Hearties - hello my friends

Aft - toward the rear of the ship.  Short for after.

Avast - "Who goes there?"

Belay - stop that or quit talking.

Bilge - expression that meant silly or foolish talk. (The bilge of a ship or the lower part fills with stinking bilge water.)

Black spot - to accuse another pirate of wrong doing or mark him for death

Blimey- means surprise

Booty - loot

Buccaneer - Caribbean pirates

Bucko - my friend

Cap'n - short for captain

Shanty - a sailor's work song

Chest - a treasure container

Crow's nest - a lookout or small platform near the top of a sailboat's mast

Cutlass - a curved sword or a traditional pirate's weapon

Davy Jone's locker - the bottom of the sea

Deadlights - eyes

Dead men tell no tales - excuse for leaving no survivors

Fair winds - goodbye and good luck

Feed the fish - men being thrown into the sea dead or alive

Gangway - "Get out of my way!"

Grub - food

Flogging - Punishment by caning

Hands - the crew of a ship

Jack tar or tar - a sailor

Jollyboat - a small boat or little dinghy

Jolly roger - the pirates' skull-and-crossbones flag. It was an invitation to surrender and be treated well.  A red flag meant "no quarter" or chance to surrender.

Lad, lass, or lassie - someone younger than you

Landlubber or just lubber - a non-sailor.

Letters of marque - papers issued by a national government during wartime which allowed a privately owned ship to raid ships of hostile nations. A ship bearing such letters, and operating within their limits, is a privateer rather than a pirate.  The problem was that privateers often ignored the marque and did what they pleased.  Also, letters of marque weren't  always honored by the government that issued them.  

Maroon - to leave a victim on a deserted island with usually only a gun and a little water.  Pirates often suffered this fate for going against the ship's articles or rules.

Me - pirates often said this word instead of "my"

No quarter - surrender will not be accepted

On the account - a pirate was said to be this

Pillage - to raid and rob

Pirate - a seagoing robber that was not under orders from a country like a privateer 

Port - the left side of the ship when you are facing toward her prow.

Poxed - diseased. Used as an insult.

Privateer - a ship or crew bearing a letter of marque with orders from a country to attack hostile nations' ships.  

Sail ho - to see a sail over the horizon 

An old salt  - an experienced seaman

Scurvy - a disease due to lack of vitamin C which often afflicted sailors.  Often used as an insult.

Sea dog - an experienced seaman

Shiver me timbers - expression of surprise or strong emotion

Starboard - the right side of the ship when you are facing toward her prow.

Walk the plank - a victim, usually blindfolded or with bound hands, is forced to walk a plank off of the side of a boat

Weigh anchor - to haul the anchor up to leave port