The door card is the name given to the first visible card on a poker table that is either placed on the board or dealt out to a player. The card that is called the door card, changes according to the type or format of poker that is being played.
In a stud game, the first face-up card handed to a player is known as the door card. This changes with the variation in format to a Hold’em game where the first card to placed face-up on the board, amongst the community cards, in the flop is known as the door card.
In draw poker, the door card is the name given to the bottom card held by a player that can be seen occasionally at the bottom of the player’s hand. Normally, the card is accidently seen by a player however sometimes, players are known to deliberately show others their cards in order to give them an idea, or bluff others into thinking about what they might be holding. This is not an uncommon occurrence, especially in lowball games.