Dark:

Refers to an action that is taken before receiving information to which the player would normally be entitled.

Dead Blind:

Is a blind that is not "live". In this the player posting it does not have the option to raise if other players just call. Usually refers to a small blind posted by a player entering, or returning to, a game (in a position other than the big blind) that is posted in addition to a live blind equal to the big blind.

Dead Hand:

A player's hand that is not entitled to participate in the deal for reasons like having been fouled by touching another player's cards, being found with the wrong number of cards, being dealt to a player who did not make the appropriate forced bets, etc.

Deadwood:

The muck.

Decloak:

To raise after having slow played for a while, making it clear that you were, in fact, slow playing.

Deuce:

This refers to a 2-spot card. Or to any of the various related uses of the number two, such as a $2 limit game, a $2 chip, etc.

Deuce-to-Seven:

This is a method of evaluating low hands.

Discard:

To take a previously dealt card out of play. The set of all discards for a deal is called the "muck" or the "deadwood".

Dog:

I bet you can come up with 10 different usages for that word. Well, you are not far behind here. It means an underdog - a player with a smaller chance to win than another specified player. Frequently used when the exact odds are expressed.

Donation:

A call made by a player who only expects to lose, either out of boredom or irrational optimism. I guess then you must be reaching new highs of boredom!

It is used to describe an inexperienced, unskilled, or foolish poker player. I played that hand like a donkey. Also "fish".

To play a hand poorly. Do that often and you’ll be the next ‘donkey’ in the line!

It’s not a card that shows you the exit door but quite oppositely, it’s the first card dealt face up to each Player in Seven Card Stud.

Refers to any of the several community card game variants (usually Texas hold 'em) in which two separate boards of community cards are dealt simultaneously, with the pot split between the winning hands using each board.

It refers to any of the several Draw poker games in which the draw phase and subsequent betting round are repeated twice.

In a big bet game, if you bet all of your's chips on one hand against a single opponent(who has an equal or larger stack) and win, thereby ‘doubling’ your stack.

A card that is dealt facedown.

Refers to the green felt surface of a poker table no longer obscured by chips because wither you are ‘All in’ or have lost all of your money.

Believe me this has nothing to do with smoking! It means to pull chips away from the pot to indicate that you don't have enough money to cover the bet. If you win, the amount is ignored. If you lose, you must cover the amount from your pocket.

It is as dead as it reads. It means having no possible cards that can beat your opponent.

Not drawing dead; that is, drawing to a hand that will win if successful.

Not drawing completely dead, but chasing a draw in the face of poor odds.

To fold. Also, to lose a particular amount of money. To drop ones cards indicates that one is in or out of a game.

A side pot with no money. Created when a player goes all in and is called by more than one opponent, but not raised. Bluffing into a dry pot is a play that cannot possibly earn a profit, so doing so is considered foolish.
It may also be unethical, because it serves to protect the all-in player at the expense of the better and the other players, and so is a form of collusion.