Definition of rack (noun)

A geometric form, usually aluminum, wooden or plastic, used to assist in setting up balls in games like eight-ball, nine-ball, and snooker. The rack allows for more consistently tight grouping of balls, which is necessary for a successful break shot. In most games a triangle-shaped rack capable of holding fifteen balls can be employed, even if the game calls for racking less than a full ball set, such as in the game of nine-ball. For further information, see the Rack (billiards) main article.
In some games, refers to a single frame.

24 Random Essential Billiards Terms

Three equally spaced diamonds are normally between each pocket on a pool table. On a carom table, the pockets themselves are replaced by additional diamonds. Diamonds get their name from the shape of the markings traditionally used; though many today are round, square, etc., these rail markings are still referred to as "diamonds".
Also known as a Dead cushion. A cushion that has either lost a degree of elastic resiliency or is not firmly bolted to the frame, in both cases causing balls to rebound with less energy than is normal.
A 7 inch (17.8 cm) square box drawn on a balkline table from the termination of a balkline with the rail, thus defining a restricted space in which only 3 points may be scored before one ball must be driven from the area. It developed to curtail the effectiveness of the chuck nurse, which in turn had been invented to thwart the effectiveness of the Parker's box in stopping long, repetitive runs using the anchor nurse.
A well calculated successful slop shot that is usually hit a little harder than it should be and results in a pocketed ball or two without any fouls.
This is a location where a player can go inexpensively to refine their pool skills. These establishments began as horserace betting houses, and are still often filled with games involving money action. If you get thirsty, many pool halls offer cold refreshments, however, be careful you are not there just for the refreshments. In that case, you may as well be playing at a bar with a bent cue on a rain table.
A material, usually leather, placed on the end of a cue stick that comes in contact with the cue ball.
The white ball struck by the cue (and so used to strike other colored, numbered, object balls) during play.
To bungle a shot in a manner that leaves the table in such a fortuitous position for the opponent that there is a strong likelihood of losing the game or match. Contrast sell out.
This is to watch a match with such intensity that there is worry, usually because of a wager on the game.
In snooker, the highest-value colour ball on the table, being worth seven points. In some (especially American) snooker ball sets it is numbered "7" on its surface.
The black ball (usually numbered "8") in the eight-ball variant game blackball (and its variants); also the common British term for the slightly larger but otherwise identical 8 ball in a kelly pool set (a.k.a. American or WPA pool set).
A player of cue sports.
To intentionally miss a shot (that results in a foul) in order to create a position for the cue ball that makes it hard for the other player to execute their shot. Not to be confused with a "Safety", since a safety is a legal hit.
Describes the propensity of pockets to more easily accept an imperfectly aimed ball shot at a relatively soft speed, that might not fall if shot with more velocity ("that ball normally wouldn't fall but he hit it at pocket speed"). The less sensitive to shot-speed that a pocket is, the "faster" it is said to be.
Describes the velocity of an object ball shot with just enough speed to reach the intended pocket and drop. "Shoot this with pocket speed only, so you don't send the cue ball too far up-table."
Chiefly British: Short for side spin. In Canadian usage, the term is sometimes used as a verb, "to side".
(Jack and Jill) Mixed doubles match (each team has one male and one female).
A term used to indicate balls that are frozen, or close enough that no matter from which angle they are hit from the combination will send the outer ball the same direction. "Are the 2 and 7 pointing at the corner?? Okay, I'll use that duck to get position way over there."
This is any game of pool played with money on the line. You can "put some action" on the game.
The three-foul rule describes a situation in which a player is assessed a defined penalty after committing a third successive foul. The exact penalty, its prerequisites and whether it is in place at all, vary depending on the games. In nine-ball and straight pool, a player must be the told he is on two fouls in order to transgress the rule, and if violated, results in a loss of game for the former and a special point penalty of a loss of fifteen points (plus one for the foul itself) in the latter together with the ability to require the violator to rerack and rebreak. In Irish standard pool and English billiards, it is a loss of game if a player commits a third foul while shooting at the black. In snooker, three successive fouls from an unsnookered position result in forfeiting the frame. Repeat fouls from a snookered position are quite common - Dave Harold holds the record in a competitive match, missing the same shot 14 successive times.
In blackball, a situation where the player cannot see any of the balls she/he wants to hit due to obstruction by other balls or the knuckle of a pocket. The player must call "total snooker" to the referee, which allows a dispensation to the player from having to hit a cushion after contacting the object ball, which is otherwise a foul.
A joint type in which the butt and shaft screw together in a tight lock, resulting in a better shot with more hitting power.
This is another name for One Pocket pool.
In eight-ball and related games, describes the situation in which neither player has yet claimed a suit (group) of balls. Often shortened to simply open: "Is it still an open table?" "Yes, it's open."
This is a player who has the ability to make difficult shots in one pocket, because they are likely proficient at other pool games first.
An exhibition shot designed to impress either by a player's skill or knowledge of how to set the balls up and take advantage of the angles of the table; usually a combination of both. A trick shot may involve items otherwise never seen during the course of a game, such as bottles, baskets, etc., and even members of the audience being placed on or around the table.