. Extras See: Mandatory Extras. EXtreme Gammon A neural-net backgammon program introduced in 2009. ] Simplified backgammon, in which each player starts with two checkers on his one, two, and three-point, and three checkers on his four, five, and six-point. See How to Play Eureika. Exposed Checker A blot within range of a direct hit. Eureka [Also spelled “Eureika”. Establish a Point Make a point.

You face your opponent on a tiled map where you take turns trying to destroy each others base. There is somewhat of a learning curve to figure out which type of decks and tactics are strongest for a particular map. Pox Nora is a blend between a card game and a tactics game. Cars are used to activate spells, artifacts and units on the battlefield.

Automatic Doubles An optional rule in money play: If both players throw the same number on the first roll of a game, the stakes are doubled. Attack Zone See: Zone of attack. Attacking Game Blitz (1). Asset A feature that contributes to the strength of a position, such as made points and flexibility. Automatics Automatic doubles. Players usually agree to limit the number of automatic doubles to one per game. The doubling cube is turned to 2 and stays in the middle. . Awkward Number A dice roll which forces a player to leave a shot or break a valuable point (2).

MET Match equity table. Website: Motif Plays Backgammon. You must either keep track of the number of pips moved or make a compensating shift elsewhere on the board. See: How to Play Moultezim. There is no hitting and one checker by itself controls a point (1). Mobility The degree to which a position permits dice rolls to be played freely while maintaining the position’s key features. . Website: Meyer Dice Tube. Traditionally, matches are played to an odd number of points (3, 5, 7, etc. ” Middle Game The main body of the game, which begins after the players have settled on their initial game plan. Monte Carlo Location of the annual World Championship of backgammon. The first column and row represent the Crawford game. There are three types of legal moves you may make: (a) to enter a checker from the bar (your only legal move when you have a checker on the bar); (b) to move a checker forward the given number of pips (2) to an open point, possibly hitting an opposing blot; or (c) to bear off a checker, when all of your checkers are in their home board. Knowing the number and size of your market losers is an important consideration in whether or not to double. To roll the dice, you pick up the tube, quickly turn it 180 degrees, and set it back down, allowing the dice to fall through the baffles and land on the other side. Mechanic See: Dice Mechanic. Compare: Opening Game and End Game. Minor Split Moving one of your two runners from the opponent’s one-point to the opponent’s two-point or three-point. Match Winning Chances A player’s probability of winning a match. Move Off Bear off. See post by Adam Stocks. Move Out A move from the opponent’s home board to the opponent’s outer board. Match Play The method of competition used in tournaments and on many backgammon play sites. Mexican Backgammon A backgammon variant similar to Acey-Deucey (2) in which a roll of 1 and 2, called a Mexican, gives the player extra turns. Mixed Roll Two thrown dice with different numbers on their upper faces. Market Gainer [By analogy to market loser. See: Chuck Bower’s article: “A Closer Look at the Meyer Dice Tube. Move In A move from the bar to the opponent’s home board. Match Equity A player’s probability of winning a match from a given score. Mutual Holding Game A game in which both players hold advanced anchors on the opponent’s side of the board in an attempt to hinder the opponent as he tries to bring his checkers home. The doubling cube may be used except in the Crawford game. See: How to Play Mexican Backgammon. Mechanical Play A move made with little thought because it seems to be obvious. Move Down Move around the corner. Money management has two goals: to ensure that your bankroll lasts the entire session and to make playing more fun by removing some of the stress involved in dealing with money. Money Management Choosing appropriate stakes to play for so that you do not exceed your bankroll. Move Up A move forward within the opponent’s home board. Move Around the Corner A move from the opponent’s outer board to the player’s outer board. MWC Match winning chances. Mental Shift A technique used in pip counting in which you imagine that some checkers have been moved to a higher or lower point where they can be counted more easily. Market Losing Sequence Market loser. Unlike money play, you do not use automatic doubles, the Jacoby rule, or beavers in match play. Moultezim A Turkish game in which players start at diagonally opposite corners and move around the board in the same direction. A term used in the late 1990’s and early 2000’s for a style of play inspired by computer analysis. Modern Backgammon A term used in the late 1920’s and early 1930’s for the new rules of the time, including the use of the doubling cube and chouette play. A move from your outer board to your home board. Meyer Dice Tube A 9-inch clear plastic tube with baffles across the middle and capped ends that contains a pair of dice and is used to randomize dice within. Match equity tables are laid out according to the number of points each player still needs to win the match. At the end of each game, the loser pays the winner the agreed initial stake multiplied by the value of the doubling cube and further multiplied by 2 for a gammon or 3 for a backgammon (2). Market Loser A sequence of two rolls (one for you and one for your opponent) which takes a game from a position in which your opponent would accept a double to a position in which your opponent would refuse a double. See: How to Play Misere Backgammon. The value of a position in the context of the current match score and cube level, usually given in terms of match winning chances. Move The advancement of a checker according to the number showing on one of the rolled dice. You place the tube on one end with the dice lying on the bottom. Mid-Point Your thirteen-point (the opponent’s twelve-point), where you have five checkers at the beginning of the game. A mobile position strikes a balance between the made points and spare checkers. Money play backgammon is normally played using the Jacoby rule and participants may also agree to play automatic doubles and beavers. Match A series of games between two players which ends when one player acquires a predetermined number of points. Misere A backgammon variant in which the object is to be the last player to bear off all of your checkers. ] A sequence of two rolls (one for you and one for your opponent) which takes a game from a position in which your opponent would refuse a double to a position in which your opponent would accept a double. Motif A Java applet that plays backgammon. Two competitors play a series of games until one of them acquires a predetermined number of points (4). Match Equity Table A chart showing the probability of winning a match from various scores. Example: The Woolsey-Heinrich match equity table. Money Play The normal style of competition in backgammon in which games are played individually and the participants bet on the result.

Opposite of double out. Doubling Block Doubling cube. Dropper [From the server message: Player xxx drops connection. Double Game Gammon. Double Jeopardy Potential for awkward rolls both next turn and the turn after. A good distribution is compact with spares on most points. Double In To offer a double which should be properly accepted. Duplicate Dice In a rollout, the use of the same sequence of random rolls with different candidate positions. Doubling Cube A cubical block, slightly larger than a regular die, with the numbers 2, 4, 8, 16, 32, and 64 marked on its faces. DMP Double match point. Dyscommunication [Coined by Danny Kleinman in Double Sixes from the Bar. Doubles Two thrown dice with identical numbers on their upper faces. Disjointed Position A position that is poorly connected, in which a player’s army is divided into two or more groups with large gaps between them. If he accepts your double, he places the cube on his side of the board and becomes the owner of the cube. Double Shot One blot which can be directly hit two different ways, or two blots each of which can be directly hit one way. Drop Refuse a double. Double Direct Shot Double shot. Same as cashing a game. The range of game winning chances which would be a proper double and a proper take if neither player could use the cube again. See post by David Montgomery. Dutch Backgammon A backgammon variant in which the players start with all their checkers off the board. Division One of the sections in a tournament into which players are divided according to their ability and experience. It is used for keeping track of the increase in stakes of the game and the player who next has the right to double. ] The negative impact on flexibility of having spare checkers exactly six pips apart. Double Bump Double hit. Double Ducks The roll of 2-2 on the dice (double 2’s). The idea is that lucky rolls for one position will tend to be lucky for the other position as well, and luck will be less of a factor in the outcome. Double Hit To hit two opposing blots on one turn. Doubling Window The range of game winning chances which are both a proper double and a proper take. Drop Point The maximum game winning chances at which it is correct for a player to refuse a double; the point at which a player is equally well off accepting a double or refusing a double; take point. For example, a tournament might have a novice division, an intermediate division, and an open division. A player who accepts a double becomes owner of the cube and only he may make the next double in the same game. For example, when your opponent can use a 5 to hit either of two blots, his 5’s are said to be duplicated. When you offer a double, you turn the cube to its next higher value and pass it to your opponent. You don’t want too many points or too few points (candlesticks). See: How to Play Duplicate Backgammon. Double Elimination A tournament format in which a competitor continues playing until he has lost twice. Double Out To offer a double which should be properly dropped, thus taking your opponent out of the game. . Otherwise, he must accept the double and the game continues at double the previous stakes. Diversification The spreading out of your checkers to increase the number of good rolls on your next turn. Duplicate Tournament See: Duplicate Backgammon. Doubler Doubling cube. Ducks Double ducks. Distribution The arrangement of checkers among points. ] A player on a backgammon server who avoids a reduction to his rating by intentionally leaving a match he is about to lose before the result recorded. Double An offer made by one player to his opponent during the course of the game (on that player’s turn, but before he has rolled the dice) to continue the game at twice the current stakes. Draw The random pairing of competitors in a tournament to determine who will play whom or who will get byes. Double Match Point A match in which both players need just one more point (4) to win. Drop-Take In a chouette, an agreement between two players after a double by the box that one player will accept the double, the other will refuse, and they will share their combined earnings or loss. See post by Simon Woodhead. Rules that affect use of the doubling cube: automatic doubles, the Jacoby rule, and beavers. After the first double of a game, only the player who last accepted a double may make the next double. Doubling on the Come Offering a double in anticipation of a good roll. A game in which the doubling cube has reached a high enough level that a win by either player also wins the match. Duplicate Backgammon A form of tournament play in which in which multiple pairs of competitors play with the same dice rolls in separate games and compare their results. Duplication A position in which the same number can be used constructively in more than one way. The opponent may refuse the double, in which case he resigns the game and loses the current (undoubled) stakes. All else being equal, a position which duplicates the opponent’s good numbers is better than one which does not because it means the opponent has fewer good rolls in total. See: How to Play Dutch Backgammon. The cube starts in the middle with the number 64 facing up (representing a value of 1). Opposite of double in. See post by Simon Woodhead. Down An early-game move of a checker from the mid-point to the same player’s outer board.

Gammon-go for you is gammon-save for your opponent. Gammon Vigorish (Vig) The additional equity resulting from the possibility of winning a gammon. GNU Backgammon is a cooperative effort of many volunteers. See the post by Gary Wong and the tutorial by Albert Silver. Greek Backgammon Tavli. An individual player’s gammon rate is the fraction of his wins which are gammons or backgammons. Gammon-Go A situation in match play where losing a gammon has no cost, but winning a gammon is particularly valuable. Gammon Cube Jacoby rule. See post by David Montgomery. Guff (Guffy) A player’s one-point. See posts by Mary Hickey and Marty Storer. See: How to Play Gioul. Give a Little Present to Double. In money play, with the Jacoby rule in effect, gammons do not count if the doubling cube has not been turned that game. Giving for Game A statement made by a player in a chouette that he is willing to pay the captain or any other team member the full stake at which the game currently stands for the right to take over their games. Game Winning Chances The probability of winning the current game if it is played to conclusion without a doubling cube; also called cubeless probability of winning. Gin Position A position from which a player cannot lose. Examples: (a) you trail 4-away/2-away and opponent owns the cube at 2; or (b) you trail 2-away/1-away in the Crawford game; or (c) you trail 3-away/1-away after the Crawford game and the cube is at 2. Gammon-save for you is gammon-go for your opponent. Compare: Single Game and Backgammon (2). Go Out To achieve the points (4) necessary to win a match. , without a doubling cube). See: How to Play Gul Bara. Gammonish A position that has a higher than normal gammon rate. This includes intentionally distracting, confusing, or generally duping an opponent. Gammon price is computed as GP = (WG – W) / (W – L), where WG = value of winning a gammon, W = value of winning a single game, and L = value of losing a single game. Greedy Bearoff A mode in some computer programs and on some backgammon servers where the computer will automatically bear off the maximum number of checkers possible. See post by Albert Steg. See posts by David Montgomery and Ron Karr. Gammon Price The relative value of winning a gammon compared with the value of winning a single game. Gul Bara A Middle Eastern game in which a single checker controls a point (1) and doubles are very powerful. Gammon rate may refer to a particular game in progress or to backgammon games in general. Examples: (a) you lead 2-away/4-away and own the cube at 2; or (b) you lead 1-away/2-away in the Crawford game; or (c) you lead 1-away/3-away after the Crawford game and the cube is at 2. Gammon A completed game of backgammon in which the losing player has not borne off any checkers. Gammon Count The minimum number of pips a player needs to roll to bring all his checkers home and bear off his first checker, thereby avoiding losing a gammon. . The player making this offer does so because he wishes to double the box when the other players to do not. GNU Backgammon A neural-net computer program that plays backgammon (1) and analyzes positions and matches. See posts by Mary Hickey and Marty Storer. ] The opponent’s five-point, the best place to build an anchor. Girls (The Girls) A roll of 5-5 (double 5’s). Golden Point [Coined by Paul Magriel in his book Backgammon. Gioul A Middle Eastern game in which a single checker controls a point (1) and doubles are very powerful. Game Plan A strategy for winning the game. GWC Game winning chances. It is “free” software as defined by the GNU General Public License. The three major game plans are run, block, and attack. In money play, the gammon price is 50%. Gap The space or spaces between made points. A gammon is also called a double game because the winner receives twice the value of the doubling cube. Gamesmanship The use of ethically dubious means to obtain an advantage in a game. Gammon Rate The chance of a game ending in a gammon or a backgammon (2) if played to completion (i. Gammon-Save A situation in match play where winning a gammon has no value, but losing a gammon is particularly costly. G Gain a Tempo Hit the opponent and thereby deprive him of half a roll. In match play, the gammon price depends on the score of the match and the level of the doubling cube.

Double Ducks The roll of 2-2 on the dice (double 2’s). For example, a blot is in direct range of being hit if it is six points or less away from an opposing checker. . ] A player on a backgammon server who avoids a reduction to his rating by intentionally leaving a match he is about to lose before the result recorded. Doubling Block Doubling cube. You must be within six points of a blot to be able to hit it directly. Dutch Backgammon A backgammon variant in which the players start with all their checkers off the board. Distribution The arrangement of checkers among points. Dyscommunication [Coined by Danny Kleinman in Double Sixes from the Bar. See post by Simon Woodhead. Drop-Take In a chouette, an agreement between two players after a double by the box that one player will accept the double, the other will refuse, and they will share their combined earnings or loss. You don’t want too many points or too few points (candlesticks). Double An offer made by one player to his opponent during the course of the game (on that player’s turn, but before he has rolled the dice) to continue the game at twice the current stakes. Doubler Doubling cube. Duplicate Dice In a rollout, the use of the same sequence of random rolls with different candidate positions. Duplicate Tournament See: Duplicate Backgammon. Double Direct Shot Double shot. A good distribution is compact with spares on most points. Doubling on the Come Offering a double in anticipation of a good roll. Doubles Two thrown dice with identical numbers on their upper faces. A player who accepts a double becomes owner of the cube and only he may make the next double in the same game. Duplicate Backgammon A form of tournament play in which in which multiple pairs of competitors play with the same dice rolls in separate games and compare their results. Draw The random pairing of competitors in a tournament to determine who will play whom or who will get byes. See: How to Play Dutch Backgammon. Doubling Window The range of game winning chances which are both a proper double and a proper take. For example, a tournament might have a novice division, an intermediate division, and an open division. Direct Hit A hit using the number on just one die. Direct Shot A chance to hit a blot six points or less away using a single number from one die. When you offer a double, you turn the cube to its next higher value and pass it to your opponent. Double Elimination A tournament format in which a competitor continues playing until he has lost twice. Rules that affect use of the doubling cube: automatic doubles, the Jacoby rule, and beavers. Drop Refuse a double. Double Bump Double hit. See: How to Play Duplicate Backgammon. After the first double of a game, only the player who last accepted a double may make the next double. DMP Double match point. The idea is that lucky rolls for one position will tend to be lucky for the other position as well, and luck will be less of a factor in the outcome. The cube starts in the middle with the number 64 facing up (representing a value of 1). ] The negative impact on flexibility of having spare checkers exactly six pips apart. Drop Point The maximum game winning chances at which it is correct for a player to refuse a double; the point at which a player is equally well off accepting a double or refusing a double; take point. Ducks Double ducks. Disjointed Position A position that is poorly connected, in which a player’s army is divided into two or more groups with large gaps between them. Double Match Point A match in which both players need just one more point (4) to win. Double In To offer a double which should be properly accepted. The opponent may refuse the double, in which case he resigns the game and loses the current (undoubled) stakes. Same as cashing a game. Duplication A position in which the same number can be used constructively in more than one way. If he accepts your double, he places the cube on his side of the board and becomes the owner of the cube. Division One of the sections in a tournament into which players are divided according to their ability and experience. For example, when your opponent can use a 5 to hit either of two blots, his 5’s are said to be duplicated. See post by Simon Woodhead. A game in which the doubling cube has reached a high enough level that a win by either player also wins the match. Direct Range Reachable using a single number from one die. Opposite of double out. Double Out To offer a double which should be properly dropped, thus taking your opponent out of the game. Doubling Cube A cubical block, slightly larger than a regular die, with the numbers 2, 4, 8, 16, 32, and 64 marked on its faces. All else being equal, a position which duplicates the opponent’s good numbers is better than one which does not because it means the opponent has fewer good rolls in total. Diversification The spreading out of your checkers to increase the number of good rolls on your next turn. Opposite of double in. Double Game Gammon. See post by David Montgomery. Down An early-game move of a checker from the mid-point to the same player’s outer board. The range of game winning chances which would be a proper double and a proper take if neither player could use the cube again. Double Hit To hit two opposing blots on one turn. Double Jeopardy Potential for awkward rolls both next turn and the turn after. It is used for keeping track of the increase in stakes of the game and the player who next has the right to double. Otherwise, he must accept the double and the game continues at double the previous stakes. Disengage To break all contact and turn the game into a pure race. Double Shot One blot which can be directly hit two different ways, or two blots each of which can be directly hit one way. Dropper [From the server message: Player xxx drops connection.

In this game you have the opportunity to find your favorite One Piece characters in the world of Anime Pirates and build your own personal pirate crew. Pirate King is a Massively Multiplayer Online Role Playing Game that utilizes a turn-based combat system.

Control the Cube Own the cube. When your checkers move counterclockwise, your opponent’s checkers move clockwise. Cubeful rollouts more accurately simulate actual games than cubeless rollouts, but they have greater variance, so they do not converge as quickly. Cup Dice cup. The relative standing of the players’ pip counts. Correspondence Games Games played by e-mail. See posts by: Chuck Bower, Kit Woolsey, and Walter Trice. Cubeless Probability of Winning The chance of winning the game if no doubling cube is used; also called game winning chances. Crew In a chouette, members of the team who play with the captain against the box. See post by Stig Eide. See: Danny Kleinman (1980) “Cube Provocation Play”. Count Pip count. Each trial is played to the end of the game and scored plus or minus 1, 2, or 3 points (4) depending on whether gamed ended in a single game, gammon, or backgammon (2). Consolidate To reduce the number of blots a player has, frequently as a precursor to offering a double. Contact Position A game where the opposing forces have not moved past each other and where it is still possible for one player to hit or block the other. Crunched Position A position which has collapsed, with several checkers being forced to the low points (1) in the player’s home board while other checkers remain in the opponent’s territory. It is the result you would obtain if you could do a rollout an infinite number of times. You bravely maintain contact with a single checker on his one-point and deploy your other fourteen checkers where they can contain his checkers if you are able to hit one or, preferably, two of them. Count the Position To tabulate the players’ pip counts to find out who is ahead in the race and by how much. Convergence Value (of a Rollout) The value approached by a rollout as more and more trials are performed. Consolation Flight A event for players eliminated early in the main flight of an elimination tournament; sometimes called a sympathy flight. Crossover The movement of a checker from one quadrant of the board to an adjacent quadrant. After the Crawford game, the doubling cube is back in play again. See post by Chuck Bower. Crunching Position A priming game in which one side is about to collapse, but has not done so yet. Cramped Having little or no mobility. . Confetti What you sometimes get paid in if you are not careful with whom you play. And cubeful rollouts may be more susceptible to systematic error because of cube misplays. CPW Cubeless probability of winning. Cube Play The act of offering a double, or the act of accepting or refusing the opponent’s double. Connected checkers defend each other and are easily made into points (2). Cubeful Rollout A rollout performed with the doubling cube in play. Confidence Interval A range of values that contain, with a certain probability, a rollout’s convergence value. Cube Ownership Which player has the right to make the next double. Cube Provocation Play: An error in checker play that induces the opponent to double on his turn. Crawford Game The first game in a match after either player comes to within one point (4) of winning. Coup Classique A win from the seemingly unwinnable position in which your opponent has borne off twelve checkers and has just three checkers remaining on his two-point. In match play, cubeful equity corresponds to the probability of winning the match from the current position. Current Stake The initial stake multiplied by the value of the doubling cube. That means some trials will end in a dropped double and others will end with the cube at 2, or 4, or even higher. This one game without doubling is called the Crawford Game. Cube Action All of the cube decisions associated with a given position, namely: (a) whether the player on roll should double, and (b) whether his opponent should accept the double, refuse the double, or possibly beaver. A position which is well-connected will tend to stay well-connected. Cube Decision The choice of whether or not to offer a double, or the choice of whether to accept, or refuse a double that has been offered. Cubeful equity considers the current value of the cube, cube ownership, and the potential for future doubles. This is a value between -3 and +3 and is equal to P(W) + P(Wg) + P(Wbg) – P(L) – P(Lg) – P(Lbg), where P(W) is the probability of winning the game, P(Wg) is the probability of winning a gammon (or backgammon), P(Wbg) is the probability of winning a backgammon, P(L) is the probability of losing the game, P(Lg) is the probability of losing a gammon (or backgammon), P(Lbg) is the probability of losing a backgammon. Consolation Division Consolation flight. See posts by Chuck Bower and others (2007). Examples are Wisecarver Paradox positions. Cube Proxy A player in a chouette who temporarily handles the cube for another while that player is away from the game. See post by Ilia Guzei. Crossover Count The total number of crossovers needed to get all your checkers home and then borne off. The player with the lower pip count is said to be ahead in the count. Cube in the Middle See: Centered Cube. A correct checker play that leads the opponent to correctly double when at least one other play is available after which the opponent would be wrong to double. Connected Position A position in which all fifteen of a player’s checkers are located within a short distance of each other. Crawford Rule [Named for John R. Crunch The forced evacuation of desirable points (2) due to the lack of alternate plays; in particular, a position in which you are forced to bury checkers deep within your home board. Consultation Advice offered by the crew to the captain in a chouette. Only the player who controls a point may move additional checkers to that point. Connectivity The degree to which all of a player’s checkers work together as a unified army without large gaps between them. Cube Reference Position A position for which the correct cube action is known which serves as a standard by which other similar positions may be judged. Because cubeless rollouts do not include cube play, they do not perfectly simulate a game, but cubeless rollouts have less variance and less systematic error than cubeful rollouts. Cubeless Equity The value of a position if the game is played without a doubling cube. Counterplay Possibilities for retaliation, switching from a defensive posture to an offensive posture. Cubeful Equity In money play with the doubling cube, the absolute value of a position to one of the players compared to the initial stake being played for. ] A standard rule of match play. Cover a Blot To add a second checker to a blot, thereby making the point. Cube Handling The art or skill of making cube decisions. Counterclockwise The direction your checkers move around the board when they are set up to bear off to the right. For example, with a 95%-confidence interval, there is only a 5% chance that performing the same rollout an infinite number of times will yield a result outside the interval. At the start of the game, the cube is in the middle and either player may double. The art or skill of making cube decisions. After one player accepts another’s double, he owns the cube, and only that player may make the next double. When the leading player comes within one point (4) of winning the match, the following game is played without a doubling cube. The ploy could be intentional, an attempt to get the opponent to double too early, but the term “cube provocation play” is often used mockingly to refer to an obvious error. Cube [Noun. Winning a coup classique is especially satisfying for you and maddening for your opponent. Control a Point A player controls a point (1) if he has two or more checkers on that point. Cubeless Rollout A rollout performed without using a doubling cube. ] To offer a double. The rules of match play say that the doubling cube may not be used during the Crawford game. This can happen if the better play produces a more volatile position — the opponent is forced to double because he has too many market losers. All appropriate cube decisions are made as the position is played out. Contain a Checker To prevent an opposing checker from escaping to its own side of the board by blocking it or hitting it and sending it back.

See post by Stephen Turner. Turn the Crank To offer a double. Trois-Point Traditional name for the three-point. Two-Sided Bearoff Database A bearoff database with the correct equity for each possible combination of two opposing bearoff positions. A two-sided database is more accurate than a one-sided database, but requires considerably more room. Trice Count Another name for the effective pip count, a concept developed by Walter Trice who wrote extensively about it. Turner’s Formula A simple formula devised by Stephen Turner for estimating the match equity (1) at a given score. Trice Triangle [Named for Walter Trice. ” Triple Game Backgammon (2). Tutor Mode A mode available in some backgammon-playing programs which allows the computer to evaluate your moves as you make them and alert you to any errors it thinks you made. . Expressed as a percent, the leader’s match equity E = 50 + (24/T + 3) * D, where T is the number of points (4) the trailer still needs and D is the difference in scores. See post by Gregg Cattanach. Turn the Cube To offer a double. The French name for “backgammon. Turn The sequence of actions that each player takes in alternation. One turn consists of: (a) possibly offering a double; (b) rolling the dice; (c) playing the roll; and (d) picking up the dice. Four separate equities are recorded for each position: three cubeful equities (one for each state of the doubling cube), and one cubeless equity. It has the lowest wastage of any position with all 15 checkers still on the board. Players score points for making specific plays or moving their checkers into certain configurations. Twist the Cube To offer a double. Two-Point The second point (1) in a player’s home board, adjacent to the one-point; also called the deuce-point. A truncated rollout has more systematic error than a full rollout but is faster because each trial is shorter, and a truncated rollout has less variance so fewer trials are required to converge on a result. Truncated Rollout A rollout which is not played to the end of the game. See: How to Play Trictrac. ] The ideal position to aim for during bear-in, consisting of: 7 checkers on your six-point, 5 checkers on your five-point, and 3 checkers on your four-point. Turn the Corner Move from the opponent’s outer board to your own outer board. Instead, the position is rolled out a given number of plies (the horizon of the rollout) and estimates of the equities of the resulting positions are averaged together. Compare: Janowski’s Formula and Neil’s Numbers. Trictrac A game popular in French high society prior to the Revolution.

Cube Handling The art or skill of making cube decisions. Cubeless Probability of Winning The chance of winning the game if no doubling cube is used; also called game winning chances. The ploy could be intentional, an attempt to get the opponent to double too early, but the term “cube provocation play” is often used mockingly to refer to an obvious error. The art or skill of making cube decisions. Cube in the Middle See: Centered Cube. Examples are Wisecarver Paradox positions. . Cup Dice cup. After one player accepts another’s double, he owns the cube, and only that player may make the next double. This can happen if the better play produces a more volatile position — the opponent is forced to double because he has too many market losers. See: Danny Kleinman (1980) “Cube Provocation Play”. Cube Play The act of offering a double, or the act of accepting or refusing the opponent’s double. Cube Ownership Which player has the right to make the next double. Current Stake The initial stake multiplied by the value of the doubling cube. Because cubeless rollouts do not include cube play, they do not perfectly simulate a game, but cubeless rollouts have less variance and less systematic error than cubeful rollouts. This is a value between -3 and +3 and is equal to P(W) + P(Wg) + P(Wbg) – P(L) – P(Lg) – P(Lbg), where P(W) is the probability of winning the game, P(Wg) is the probability of winning a gammon (or backgammon), P(Wbg) is the probability of winning a backgammon, P(L) is the probability of losing the game, P(Lg) is the probability of losing a gammon (or backgammon), P(Lbg) is the probability of losing a backgammon. Cube Provocation Play: An error in checker play that induces the opponent to double on his turn. Each trial is played to the end of the game and scored plus or minus 1, 2, or 3 points (4) depending on whether gamed ended in a single game, gammon, or backgammon (2). Cubeless Equity The value of a position if the game is played without a doubling cube. See post by Ilia Guzei. A correct checker play that leads the opponent to correctly double when at least one other play is available after which the opponent would be wrong to double. Cube Reference Position A position for which the correct cube action is known which serves as a standard by which other similar positions may be judged. Cube Proxy A player in a chouette who temporarily handles the cube for another while that player is away from the game. Cubeless Rollout A rollout performed without using a doubling cube. See post by Chuck Bower. At the start of the game, the cube is in the middle and either player may double. See posts by Chuck Bower and others (2007).

See: How to Play Duplicate Backgammon. You don’t want too many points or too few points (candlesticks). Doubling Cube A cubical block, slightly larger than a regular die, with the numbers 2, 4, 8, 16, 32, and 64 marked on its faces. Ducks Double ducks. . Doubling on the Come Offering a double in anticipation of a good roll. Opposite of double in. Dice Combination One of the 36 possible rolls using two dice. See post by David Montgomery. DMP Double match point. Same as cashing a game. See: How to Play Dutch Backgammon. Dyscommunication [Coined by Danny Kleinman in Double Sixes from the Bar. Direct Range Reachable using a single number from one die. Digital clocks typically have a time delay feature which makes them particularly well suited for backgammon. Double Shot One blot which can be directly hit two different ways, or two blots each of which can be directly hit one way. Duplicate Dice In a rollout, the use of the same sequence of random rolls with different candidate positions. After the first double of a game, only the player who last accepted a double may make the next double. Double An offer made by one player to his opponent during the course of the game (on that player’s turn, but before he has rolled the dice) to continue the game at twice the current stakes. Opposite of double out. Rules that affect use of the doubling cube: automatic doubles, the Jacoby rule, and beavers. The cube starts in the middle with the number 64 facing up (representing a value of 1). Dice cups make it possible to shake the dice thoroughly before rolling them, ensuring a random roll. Drop Refuse a double. Double Jeopardy Potential for awkward rolls both next turn and the turn after. Drop Point The maximum game winning chances at which it is correct for a player to refuse a double; the point at which a player is equally well off accepting a double or refusing a double; take point. See post by Simon Woodhead. Dice Tube See Meyer dice tube. For example, when your opponent can use a 5 to hit either of two blots, his 5’s are said to be duplicated. Dutch Backgammon A backgammon variant in which the players start with all their checkers off the board. The range of game winning chances which would be a proper double and a proper take if neither player could use the cube again. Double Ducks The roll of 2-2 on the dice (double 2’s). Doubles Two thrown dice with identical numbers on their upper faces. There is often a ridge around the inside of the open end designed to trip up the dice as they leave the cup. A game in which the doubling cube has reached a high enough level that a win by either player also wins the match. Disengage To break all contact and turn the game into a pure race. Double Bump Double hit. Dice Manipulation Any unfair means used to influence the roll of the dice. The idea is that lucky rolls for one position will tend to be lucky for the other position as well, and luck will be less of a factor in the outcome. Presumably dice manipulation is harder when dice are rolled from a cup. See post by Simon Woodhead. ] Two small cubes, each with faces marked with spots (pips (1)) representing the numbers 1 to 6. Disjointed Position A position that is poorly connected, in which a player’s army is divided into two or more groups with large gaps between them. Doubling Window The range of game winning chances which are both a proper double and a proper take. Duplicate Tournament See: Duplicate Backgammon. For example, a tournament might have a novice division, an intermediate division, and an open division. ] A player on a backgammon server who avoids a reduction to his rating by intentionally leaving a match he is about to lose before the result recorded. Drop-Take In a chouette, an agreement between two players after a double by the box that one player will accept the double, the other will refuse, and they will share their combined earnings or loss. A player who accepts a double becomes owner of the cube and only he may make the next double in the same game. Die Singular of dice. The opponent may refuse the double, in which case he resigns the game and loses the current (undoubled) stakes. See post by Kit Woolsey. A display shows 00:00 when a player has run out of time. Distribution The arrangement of checkers among points. A good distribution is compact with spares on most points. Doubling Block Doubling cube. Double Match Point A match in which both players need just one more point (4) to win. Down An early-game move of a checker from the mid-point to the same player’s outer board. Duplication A position in which the same number can be used constructively in more than one way. Division One of the sections in a tournament into which players are divided according to their ability and experience. It is used for keeping track of the increase in stakes of the game and the player who next has the right to double. Otherwise, he must accept the double and the game continues at double the previous stakes. Dice Mechanic A person skillful in the use of unfair means to control the dice. You must be within six points of a blot to be able to hit it directly. If he accepts your double, he places the cube on his side of the board and becomes the owner of the cube. All else being equal, a position which duplicates the opponent’s good numbers is better than one which does not because it means the opponent has fewer good rolls in total. Double Elimination A tournament format in which a competitor continues playing until he has lost twice. Double In To offer a double which should be properly accepted. Direct Hit A hit using the number on just one die. Duplicate Backgammon A form of tournament play in which in which multiple pairs of competitors play with the same dice rolls in separate games and compare their results. Direct Shot A chance to hit a blot six points or less away using a single number from one die. Digital Clock An electronic chess clock with digital displays showing the time remaining for each player. When you offer a double, you turn the cube to its next higher value and pass it to your opponent. ] The negative impact on flexibility of having spare checkers exactly six pips apart. Dilly Builder A spare checker which bears only on points deep in a player’s home board. Dice [Plural of die. Dice for backgammon usually have rounded corners so they roll more easily. Double Game Gammon. Dropper [From the server message: Player xxx drops connection. Double Direct Shot Double shot. For example, a blot is in direct range of being hit if it is six points or less away from an opposing checker. Diversification The spreading out of your checkers to increase the number of good rolls on your next turn. Doubler Doubling cube. Double Out To offer a double which should be properly dropped, thus taking your opponent out of the game. Double Hit To hit two opposing blots on one turn. Draw The random pairing of competitors in a tournament to determine who will play whom or who will get byes. Dice Cup A container, usually made of leather, plastic, or wood, used for shaking and rolling dice. You throw a pair of dice at the start of each turn, and move your checkers according to the numbers thrown.