Definition of cluster

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

24 Random Essential Billiards Terms

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.
This is the act of looking over the stack, pile of balls in the middle of the table, to see if there are any opportunities in the game of one pocket.
A shot where the cue ball must hit the object ball so as to make it travel out of a straight line, at a different angle, toward its destination.
Same as gapper
In certain carom billiards games, any shot in which the cue ball is sucessfully caromed off an object ball to strike another object ball (with or without contacting cushions in the interim) is a considered a billiards shot.
The act of setting up the balls for a break shot. In tournament play this will be done by the referee, but in lower-level play, players either rack for themselves or for each other depending on convention.
Sometimes called a snake shot. A carom billiards shot, common in three-cushion billiards, where the cue ball is shot with reverse english at a relatively shallow angle down the rail, and spins backwards off the adjacent rail back into the first rail.
A pool ball that was meant to go into the pocket, but got caught up by the jaw and ended up bouncing back and forth before stopping short of the pocket.
Slang term for the cue ball.
The non-red colored ball meant to be pocketed in a game of snooker, or the next ball meant to be pocketed in a particular game.
Competition between an individual player and an individual opponent, as opposed to team play such as scotch doubles and other multi-player variants.
A team play format in which an individual player from the home team plays a race against an individual player from the visiting team, and then is finished for that match. Several large leagues use this format, including APA/CPA and USAPL.
Nine Ball is a rotation game so a player must hit the lowest numbered ball first.
The object of the game is pocket the 9-ball on any legal shot.
A slang term for a cue, usually used with "piece", as in "that's a nice piece of wood".
A barrel is how much money per game a player is betting. As in, "I have ten barrels at $20 a game".
During a set if the opponent does not win a single game, they are said to have been skunked.
Also shortstop, short-stop. This is a player that is excellent at pool, but tends to fall short of number one. A shortstop is the best player relative to a particular scene. A second-tier professional who is not (yet) ready for World Championship competition. It can also be applied by extension to a player who is one of the best in a region but not quite good enough to consistently beat serious road players and tournament pros. The term was borrowed from baseball.
Describes the propensity of a player losing small sums of money at gambling to suddenly sharply increase the stakes; often continuing to lose until broke. Compare Chasing one's money.
A type of nurse used in carom billiards games. With one object ball frozen to a cushion and the second object ball just slightly away from the rail, the cue ball is gently rebounded across the face of both balls, freezing the away ball to the rail and moving the frozen ball away the same distance its partner was previously, resulting in an identical but reversed configuration, in position to be struck again by the cue ball from the opposite side.
This is a special shaped leather or plastic bottle that is used on the table during play in special pocket games.
(Chiefly British) Said of an object ball that can easily be reached by the cue ball, or of a pocket that can easily be reached by a selected object ball, usually directly (i.e. without intervening kick, bank, carom, kiss or combination shots).
This is a play where the shot of the cue ball is meant to end up in a certain place to loose your turn, but makes the next attempt difficult for your opponent. The shot is turned over, but will often times lead to a foul, giving you the ball back with a different view or ball in hand. This "safety" play is important if your shot isn't ideal, and you are likely to turn the ball over anyway.
The situation arising in many pool games where a ball is spotted to the table's foot spot or some other specific location and the cue ball must be shot from the kitchen or the "D". There are diamond system aiming techniques for pocketing such shots without scratching the cue ball into a pocket.
In the game 9 Ball, making the nine ball early with a legal shot, but not on the break.
This term is much like rain table and refers to a table is playing soggy due to humid conditions.