Definition of session

Principally US: One or more sets, usually in the context of gambling. See also ahead race (a.k.a. ahead session) for a more specialized usage.
Principally British: Any of a group of pre-determined frames played in a match too long to be completed within a single day's play. A best of 19 frame match, for example, is generally played with two "sessions", the first composed of nine frames, the second of ten. This term is generally used only in the context of professional snooker, as matches at the amateur level are rarely played over more than nine frames. Longer matches can be split into three or four sessions.
In the APA League, session refers to the season in which League play took place. There are three sessions in each League Year-Summer Session, Fall Session and Spring Session.

24 Random Essential Billiards Terms

Used in snooker in reference to the position of the cue ball. It is above the object ball if it is off-straight on the baulk cushion side of the imaginary line for a straight pot (e.g. "he'll want to finish above the blue in order to go into the pink and reds"). It is also common to use the term high instead.
A set practice routine.
In British terminology, a bank shot.
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."
Also known as a "Dirty Defense" or "Dirty Foul". 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.
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".
This is when you win a game of one pocket on your opponents break.
This term refers to a low percentage one pocket shot.
The interlocking connection between the butt and shaft ends of a two-piece cue stick. Usually connects via means of a steel or wooden pin, and may be protected by a collar of metal or some other material, or may connect wood-on-wood.
This refers to the cluster of balls remaining in a similar position to where they were within the break.
Also winner. A shot in which the cue ball is used to pot another ball. In snooker and most pool games doing this is known as potting, pocketing or sinking the targeted ball. The term derives from this hazard winning the player points, while losing hazards cost the player points, in early forms of billiards. Whether the ball is an object ball or an opponent's cue ball depends upon the type of game (some have two cue balls). The move will score points in most (but not all) games in which hazards (as such) apply, such as English billiards (in which a "red winner" is the potting of the red ball and a "white winner" the potting of the opponent's cue ball, each worth a different amount of points).
In one pocket pool this means that you change your play based on where the count is during the game. If you are ahead you might choose more conservative shots, and if you are behind you could choose more aggressive shots.
Random method for pairing of opponents when setting up a bracket system for a tournament.
Also known as Free-stroking. This is slang for when a player begins to play untroubled and relaxed because they have built up a substantial lead.
When the cue ball is tucked behind the corner of a pocket, therefore not allowing a direct shot at the object ball.
This is when a player has scratched and the foul in one pocket calls for them to spot a ball, but not able to be spotted at the time. In this case a coin is usually placed on the side of the table to keep tabs.
The World Pool-Billiard Association (WPA) is the international governing body for pocket billiards (and also sactions rules and events for carom billiards games as well, in cooperation with other bodies). The group was formed in 1987, and was initially headed by a provisional board of directors consisting of representatives from the United States, Japan, Sweden, and Germany.
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.
A shot in which the cue ball is struck above its equator with sufficient top spin to cause the cue ball to travel forward after it contacts an object ball. When a cue ball with follow on it contacts an object ball squarely (a center-to-center hit), the cue ball travels directly forward through the space previously occupied by the object ball (and can sometimes even be used to pocket a second ball). By contrast, on a cut shot, a cue ball with follow on it will first travel on the tangent line after striking the object ball, and then arc forward, widening the carom angle.
Term for object balls in the game of Chicago that are each assigned as having a set money value; typically the 5, 8, 10, 13 and 15. In games where multiple balls must be pocketed in succession to score a point, such as cribbage pool or thirty-ball, when the last ball necessary to score has been potted, the points given is referred to as a way.
When the cue ball contacts three or more cushions in carom games.
Any shot that intentionally accounts for the elasticity of the cushions to allow a ball to bank past an otherwise blocking ball. The moving ball will sink in to the cushion very near the blocking ball giving it sufficient space to get past it or kiss off the back side of it.
Named after Chicagoan J. E. Parker, it is a 3½ × 7 inch box drawn on a balkline table from the termination of a balkline with the cushion, thus defining a restricted space in which only a set number of points may be scored before one ball must be driven from the area. Now supplanted by anchor spaces, it was developed to curtail the effectiveness of the anchor nurse, which in turn had been invented to exploit a loophole in balkline rules: so long as both object balls straddled a balkline, there was no restriction on counts, as each ball lay in a separate balk space.
On two piece cues, the area of the cue between the joint and the wrap.
The Billiards World Cup Association. The Billiards World Cup Association (BWA) was a governing body for carom billiards, like its competitor and successor, Union Mondiale de Billard. After staging several three-cushion billiards championships, BWA met its demise in 2004 due to financial problems and failing relations with the UMB, leaving the latter as the only carom governing body.