Donk

n. Abbreviation for donkey.
v. To make a poor, donkey-like play, even if successful.  "You drew out on me with 5,3 offsuit?  I can't believe how you donked me!"

Donkey

n. An unknowledgeable and thoughtless player.

Fish

n.  Bad players.  The raison d'être of both poker and fly casting.

Hammer

np.  Having unsuited starting cards of 7 and 2. This is the worst starting hand in hold'em. Often shown as a bluff to put a player on tilt.

Loose

adj.  Playing bad cards, staying in hands too long, and/or over betting.  I love loose players.

Luckbox

n.  Someone who is getting lucky at the table. Generally refers to a fish who is winning because of luck. However, the term can be applied to anyone who is having a lucky day.

Maniac

n.  Someone lacking self control who raises and reraises wildly, regardless of the hand.  Like a twelve-point buck, the maniac is the purpose of the hunt.

Pair

n. Two cards of the same rank, such as K♥K♠. Is weaker than two pair, stronger than any single high card.

Raise

v., n.  Form of bet where you put more money in the pot than the previous bettor.  Your opponent must either fold, match (call), or reraise.

River

n.  The fifth and final community card in hold'em, dealt face up in the middle of the table, which anyone can use as part of a hand.

Rock

n.  A player known to be very tight. Although predictable, rocks often win anyway.

Set

np.  Three of a kind, especially when composed of a pair in the hole with a third card on the board.

Shark

n.  A shark is a good player and typically wins. A shark's goal is often to simply just win money at poker, so they seek out games with a lot of fish. Basically, in the poker ecosystem, sharks feed on fish.

Tight

adj.  Selectively playing only the best hands or situations.  Following the money, not the thrills.  A tight player folds if there is no mathematical edge, he does not chase long shots for fun.

Tilt

v., adj.  Lose of emotional control and self-destructive betting.  Player may be angry, desperate to win back losses, on a testosterone rampage, or too shocked and muddled to do anything but plunge forward.  Watch for it, both in yourself and others.