Definition of extension

Any mechanical aid that serves to extend the length of the player's cue, normally added to the end of the butt either by clipping around the end or screwing into the base. Though extensions are used for pool, it is more common in snooker because of the significantly larger table size.
In a tournament where players get limited time to make their shots (common in televised matches), an extension is extra time granted before making a shot; players have a limited number of extensions in each frame.

24 Random Essential Billiards Terms

Toward the foot of the table.
This is to miss your shot but either luckily or on purpose leave your opponent with nothing to shoot at.
Same as spot
Also swan rest. A type of rest, similar to a spider in that the head is raised by longer supporting legs, but instead of a selection of grooves on the top for the cue to rest in there is only one, on the end of an overhanging neck, so that a player can get to the cue ball more easily if the path is blocked by two or more obstructing balls. Also known as the goose neck.
Either of the two shorter rails on a standard pool, billiards or snooker table. Contrast side rail/long rail.
A small clamping tip tool used to firmly hold and apply pressure to a replacement cue tip until the glue holding the tip to the ferrule has fully dried.
In snooker, the highest-value baulk colour, worth 4 points.
The white ball struck by the cue (and so used to strike other colored, numbered, object balls) during play.
A form of doubles play in which the two team members take turns, playing alternating shots during an inning (i.e. each team's inning consists of two players' alternating visits, each of one shot only, until that team's inning ends, and the next team begins their alternating-shot turn.) Effective scotch doubles play requires close communication between team partners, especially as to desired cue ball position for the incoming player. Like "english", "scotch" is usually not capitalized in this context. The term is also used in bowling, and may have originated there.
(Computerized Numerical Control) This is a special appliance used by many cue manufacturers to design the inlays on a cue to precision accuracy. Often times it is looked down upon because this technology departs from the previous standard of "handcrafting" inlays, using a pantograph tool. However, the new technology allows for much more precise cuts at a quicker pace. If you are looking to save some money and appreciate the man made designs that are computer inlayed in your cue, then CNC is the technology for you.
A denigrating slang term for the mechanical bridge.
CPA is the acronym for the Canadian Poolplayers Association. The CPA is the Canadian league of the APA (The American Poolplayers Association)
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.
To intentionally rebound the cue ball off both of the pocket points to achieve position.
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.
Same as gapper
Also known as a "power draw", means applying very powerful draw on the cue ball thereby causing the maximum amount of draw.
This is a shot where the cue ball contacts an object ball and moves it along a path, but because the cue ball is still in motion it re-contacts the object ball and pushes it in the pocket after it stops.
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.
Also the hook. In snooker, a type of mechanical bridge that has only recently been endorsed by the WPBSA to allow its use in major tournament play. It is a normal rest with the head in line with the shaft, but the last foot or so of the shaft is curved. This allows players to position the curved end around an obstructing ball that would have otherwise left them hampered on the cue ball and in need of a spider or swan with extensions, which would have less control.
This is the act of keeping your ball location advantages the way they are, and not allowing your opponent to even things out in the game of one pocket.
In snooker, a shot where a player fouls by missing the ball on altogether. The miss rule allows for his opponent to have the player play exactly the same shot again, or at least as accurately as the referee is able to reproduce the ball positions. A miss usually occurs when a player makes an unsuccessful attempt at escaping from a snooker. It is a controversial rule aimed at formally discouraging deliberate fouls. In professional snooker, a referee will almost always call a miss on any foul where the player misses the ball on altogether, regardless of how close the player comes to hitting it, however no miss can be called when either of the players requires snookers to win the frame. If a player is called for a miss three times in a single visit while not snookered, he forfeits the frame; to avoid this, players almost always play an easy hit on their third attempt, even if it is likely to leave a chance for the opponent.
This is a relatively simple machine that is used to duplicate inlay cuts within a cue so that the sizing will be accurate. When compared to the technical CNC machines, this is more like a tape measure, but when this effective tool is used to inlay a cue stick, you are getting a cue with genuine handcrafted inlays.
The precise center of the pool table.