The term backdoor is used to describe a play that results in a draw and needs additional rounds to fill up. These may be two or a higher number of rounds that may be required to complete the game. Example, in a Texas Hold 'em or 7-Card Stud game, to catch 2 consecutive cards within 2 rounds in order to fill up a flush or straight in both games in called a backdoor. When a player makes a hand away from the hand s/he wanted to make shows a backdoor move.
A backdoor hand can be made with the last 2 cards in the Texas Hold 'em or 7-Card Stud games. This kind of move can tilt the scales sometimes and is not one to be excited about. A player can say it this way... "I began with 4 Hearts while looking to make a flush, but I had to make a backdoor of 2 additional Kings which made me win" or I can't come to think about the fact that he made a backdoor straight without making other outs." If a player was meant to have an A Spade - 7 Spade, a flop comes with an A Diamond - 6 Club - 4 Spade. With a bet comes a call that when checked, gives a backdoor.