Definition of diamond

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".

24 Random Essential Billiards Terms

Chiefly British: The half of the table from which the break shot is taken. This usage is conceptually opposite that in North America, where this end of the table is called the head.
Either of the two longer rails of a billiards or pocket billiards table, bisected by a center pocket and bounded at both ends by a corner pocket. Also called a long rail.
This is to execute a shot where the cue ball is controlled perfectly and stops where you want it to exactly.
An agreement between two players in a tournament, one of whom will advance to a guaranteed money prize if the match is won, to give a certain percentage of that money to the loser of the match. Also known as a saver.
A bank shot is when the shooter (player) bounces the cue ball or the object ball (after it is hit by the cue ball) off a rail in an attempt to make the shot. A successful bank shot will result in sinking the object ball or a defense that will make it very difficult for the opponent to attempt their shot.
Describes lucky or unlucky "rolls" of the cue ball; "I had good rolls all night; "that was a bad roll." However, when said without an adjective ascribing good or bad characteristics to it, "roll" usually refers to a positive outcome such as in "he got a roll".
The roll: same as the lag.
A players skill level, ball advantage or match advantage when using a handicapping system.
0-2 Barbecue is a slang billiard term that refers to a single player loosing the first 2 matches in a double elimination tournament. This double loss results in that player being knocked out of the tournament without winning even one game.
A pool room employee who plays with a good degree of skill.
Also spider rest. A type of rest, similar to a common American-style rake bridge but with longer legs supporting the head so that the cue is higher and can reach over and around an obstructing ball to reach the cue ball. See also swan.
Also Gentleman's call. An informal approach to the "call-everything" variation of call-shot, common in bar pool. Obvious shots, such as a straight-on or near-straight shot for which the shooter is clearly aiming and which could not be mistaken for another shot, need not be called. Bank shots, kicks, caroms and combinations are usually less obvious and generally must be called, though this may depend upon the mutual skill level and shot selection perception of the players. An opponent has the right to ask what the shooter's intention is, if this is unclear.
In snooker and other British usages, a break of 50-99 points (100 points or more being called a century), which involves potting at least 12 consecutive balls (i.e. the last 3 reds with at least 2 blacks and a pink, followed by all the colours).
Principally British: In snooker, if a player wins a match without the need for the final session to be played (for example, if a player wins a best-of-25-frames match split into three sessions - two sessions of eight frames and one of nine - by a margin of say, 13 frames to 3), then they are said to have won the match "with a session to spare".
In blackball, a penalty conceded by a player after a fault. The incoming opponent is then allowed to miss twice before the faulting player is allowed another visit. Many local rules state the in-hand from the "D" or baulk (or if the opponent potted the cue ball, from anywhere) nature of the second shot is lost if a ball is potted on the first shot, that it is lost if the ball potted in the first shot was that player's last coloured ball (object ball in their group), and/or that there is only ever one shot on the black after a fault.
A player who was not shooting well during a match but suddenly turns it around and starts playing better and more accurately. Also known as "Finding a stroke" or "Found their stroke".
This is a kind of cue made of only two pieces of wood, and joined together using an advanced adhesive along the points of the cue. This connection gives the cue a flawless look and a fluid feel when shooting.
A description of play in carom billiards games in which the balls remain widely separated rather than gathered, requiring much more skill to score points and making nurse shots effectively impossible, and making for a more interesting game for onlookers. Most skilled players try to gather the balls as quickly as possible to increase their chances of continuing to score in a long run.
This is your pocket for sinking balls in a one pocket game.

1- Pocketing of the cue ball in pocket billiards. In most games, a scratch is a type of foul. "Scratch" is sometimes used to refer to all types of fouls.

2- British term/slang for Draw

An upright pin, which looks like a miniature bowling pin, cone or obelisk. Skittles, as employed in billiards games, have been so-called since at least 1634. One standardized size, for the largely Italian and South American game five-pins, is 25 mm (1 in.) tall, with 7 mm (0.28 in.) round bases, though larger variants have long existed for other games such as Danish pin billiards. Depending upon the game there may be one skittle, or several, and they may be targets to hit (often via a carom) or obstacles to avoid, usually the former. They are also sometimes called pins, though that term can be ambiguous. Because of the increasing international popularity of the Italian game five-pins), they are sometimes also known even in English by their Italian name, birilli (singular birillo). Skittles are also used as obstacles in some artistic billiards shots. #Flat, thin rectangular skittles, somewhat like large dominoes, approximately 6 in. tall by 3 in. wide, and placed upright like an obelisks on the table in specific spots, are used in the obsolescent and principally Australian games devil's pool and victory billiards. Depending upon the exact game being played, there may be one pin, or several of various colors (e.g. ten white and two black in devil's pool), and they may be targets or obstacles, most commonly the latter. They are usually made of plastic, and are increasingly difficult to obtain, even from Australian billiards suppliers. A black obelisk skittle of this sort features prominently, as a particularly dire hazard, in several scenes of sci-fi/pool film Hard Knuckle (1992, Australia). Skittles as used in billiards games date to ground billiards (13th century or earlier) played with a mace, and hand-thrown games of bowls from at least the same era using the same equipment. Ball games using a recognizable form of skittle are known from as early as ca. 3300 BCE in Ancient Egypt.
Short for left english (side), i.e. spin imparted to the cue ball by stroking it to the lefthand side of its vertical axis. Contrast right.
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."
Also bar rules, pub pool, tavern pool. Pool, almost always a variant of eight-ball, that is played by bar players on a bar table. Bar pool has rules that vary from region to region, sometimes even from venue to venue in the same city, especially in the U.S. Wise players thus ensure understanding of and agreement to the rules before engaging in a money game under bar rules. Typical differences between bar pool and tournament eight-ball are the lack of ball-in-hand after a foul, the elimination of a number of fouls, and (with numbered ball sets) the requirement that most aspects of a shot be called (including cushions and other object balls to be contacted) not just the target ball and pocket. Bar pool has evolved into this "nitpicky" version principally to make the games last longer, since bar pool is typically played on coin-operated tables that cost money per-game rather than per-hour. Competitive league pool played on bar tables, however, usually uses international, national or local/regional league rules, and is not what is usually meant by "bar pool".
A common way to keep track of games won when playing for small money is to use a coin that is placed under the rail next to the diamonds on the rail. The center diamond at the head of the table is taken as zero, and each diamond from that is considered to be one game. To go 'around the world' is to beat your opponent so badly that the coin travels all the way around the diamonds on the table.