Definition of cluster

Two or more object balls that are touching or are close together.

24 Random Essential Billiards Terms

A shot, especially common in straight pool and in some variants of blackball (but not WEPF/EPA rules), in which a player intentionally commits a foul with the object in mind of either leaving the opponent with little chance of running out or simply to avoid shooting where no good shot is presented and to do anything else would give the opponent an advantage. It is often referred to in straight pool as a "back scratch."
Also pro side of the pocket and missing on the professional (or pro) side of the pocket. Sometimes "of the pocket" is left off the phrase. To err on the side of overcutting a difficult corner pocket cut shot rather than undercutting in nine ball; "missing on the professional side of the pocket." So called because experienced players understand that on a thin cut, overcutting the object ball to a corner pocket will far more often leave the object ball in an unfavorable position for the incoming opponent than will an undercut, which often leaves the object ball sitting in front of or nearby the pocket it had been intended for on a miss. By contrast, in eight-ball, except when both players are shooting at the 8 ball, the incoming player after a miss is shooting for different object balls, so this maxim does not apply, and the opposite may be good strategy as, if the object ball stays near the pocket through an undercut, it is advantageously positioned for a subsequent turn and may block the opponent's use of the pocket.
A type of nurse shot used in English billiards in which two coloured balls are positioned on either side of the mouth of a snooker table pocket but not touching and, thus placed, can be successively contacted and scored off over and over by the cue ball without moving them.
Certain rules say you must designate your shot before taking it. Generally this is just calling the ball to be sunk in which pocket, and is not dependent on touching rails or other balls, but very well can be.
To reach a certain position in a tournament. "I placed 17th." "She will probably place in the money this time."
A pool room employee who plays with a good degree of skill.
To contact the chosen object ball in such a way to make it bank off a rail before being pocketed.
Failure to hit an object ball at all with the cue ball. In most sets of rules, this is a foul like any other. However, in some variants of bar pool a table scratch while shooting for the 8 ball is a loss of game where other more minor fouls might not be, as is scratching on the 8 ball (neither result in a loss of game in most professional rules).
By way of drift from the above definition, the term is also applied by many league players to the foul in more standardized rules of failing to drive a (any) ball to a cushion, or to pocket a legal object ball, after the cue ball's initial contact with an object ball.
By way of entirely different derivation ("scratch off the table"), it can also mean knocking the cue ball (or more loosely, any ball) completely off the table.
A combination shot, where hitting the first ball rubs it against the center connecting line of two frozen object balls throwing the second out.
A misnomer for hand talc.
This is your pocket for sinking balls in a one pocket game.
(noun) An opening in a table, cut partly into the bed and partly into the rails and their cushions, into which balls are shot (pocketed or potted).
(verb) Send a ball into a pocket, usually intentionally.
The Union Mondiale de Billard (French for World Union of Billiards) is the world governing body for carom (carambole) billiard games. The organization was founded in Madrid, Spain on 1 June 1959, and is dedicated to promoting the modern carom billiards games. The UMB monitors and controls international carom competitions and tournaments, and organizes an annual World Three-cushion Billiards Championship.
Hitting the object ball with not enough of a cut angle; hitting the object ball too full or "fat". It is a well-known maxim that overcutting is preferable to undercutting. See also professional side of the pocket.
The number of balls pocketed in an inning in pool (e.g., a run of five balls), or points scored in a row in carom billiards (e.g., a run of five points). Compare British break (sense 2), which is applied to pool as well as snooker in British English.
This is a style of playing a pool game with a partner playing on your team. You can either take turns or play in a tag team style. This works well when there are a lot of people around that want to play.
A form of team play in which two players compete against another team of two players in any given frame or match. In a doubles game, the first player from the breaking team is the only one who shoots during the opening inning, with control of the table passing to a member of the opposing team at the end of that inning, then upon the end of the opponent's inning to the doubles partner of the original player, and next to the second opponent, play proceeding in this doubly alternating manner until concluded. Contrast Scotch doubles.
To take one's two-piece cue stick apart. When done before a game's conclusion, it often indicates that the game is conceded.
In the UK, a long-distance shot played to pot a ball close to a pocket with heavy top spin, so that when the cue ball hits the cushion it bounces off but then stops due to the counteraction of the spin. It is not common in competitive play, being more of an exhibition shot.
A Carom game with lines drawn to form rectangles that restrict play and reduce the potential for high runs.
An unintentional and often barely perceptible curve imparted to the path of the cue ball from the use of english without a level cue. Not to be confused with a swerve shot.
Also spot-stroke, spot hazard. A form of nurse shot in English billiards, in which the red ball, which must be spotted to a specific location after every time it is potted before another shot is taken, is potted in such as way as to leave the cue ball in position to repeat the same shot, permitting a skilled player to rack up many points in a single break (series of shots in one visit).
To intentionally rebound the cue ball off both of the pocket points to achieve position.
The person who is a provider of all or part of a player's stake (money) for a gambling session in which one is not a player.
(Jack and Jill) Mixed doubles match (each team has one male and one female).