Definition of the d

A semicircle with an 11½ inch (291 mm) radius, drawn behind a snooker table's baulk line, centred on the middle of the line, and resembling the upper case letter "D" in shape. The "D" is also used in English billiards and sometimes also in blackball and other pool games played on British-style tables.

24 Random Essential Billiards Terms

Inadvertent english placed on the cueball by a failure to hit it dead center on its horizontal axis. It is both a common source of missed shots and commonly overlooked when attempts are made to determine the reason for a miss. In UK parlance this is usually called 'unwanted side'.
Having the cue ball stop precisely where intended.
Having the cue ball stop at or near the center of the table on a forceful break shot (the breaking ideal in many games such as nine-ball);
The normal phenomenon where the object ball is pushed in a direction very slightly off the pure contact angle between the two balls. Caused by the friction imparted by the first ball sliding past or rotating against the other ball.
A pool cue designed for breaking. Along with sometimes having unusual weight or balance to build maximum speed for the cue ball, some break cues have stiffer shafts and special breaking cue tips to transfer energy more efficiently to the cue ball.
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.
Also littles, little ones, little balls. In eight-ball, to be shooting the solid suit (group) of balls (1 through 7); "you're little, remember", "you're the little balls" or "I've got the littles". Compare small, solids, reds, low, spots, dots, unders; contrast big.
This is a type of shot that is executed by an object ball caroming off of another object ball in order to gain the pocket.
Also known as back spin, a type of spin applied to the cue ball by hitting it below its equator, causing it to spin backwards even as it slides forward on the cloth. Back spin slows the cue ball down, reduces its travel, and narrows both the carom angle after contact with an object ball, and angle of reflection off a cushion. There are several variant terms for this, including "bottom" and "bottom spin" in the US and "screw" in the UK. Draw is thought to be the first spin technique understood by billiards players prior to the introduction of leather tips, and was in use by the 1790s.
This refers to a shot that travels on a shallower path due to the english placed on it. This is to come up on the near side of a pocket on a bank shot.
All-Africa Pool Association. The AAPA is a member of the WPA.
Same as foot spot. Chiefly British today, but also an American usage ca. World War I.
Also straight eight-ball. Same as bar pool. Not to be confused with the games of straight pool or straight rail.
A players skill level, ball advantage or match advantage when using a handicapping system.
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).
A tactic employed in UK eight-ball pool in which a player calls and pots one of the balls in a favorably lying set, then plays safe, leaving as many of his/her well-placed balls on the table as possible, until the opponents commits a foul or leaves a chance that the player feels warrants an attempt at running out.
A shot in which the cue ball is potted after caroming off another ball. In snooker and most pool games doing this would be a fault (foul), but the move will score points in many games in which hazards (as such) apply, such as English billiards, or in the final or game point in Cowboy pool. The term derives from this hazard costing the player points in early forms of billiards.
This is a creative game played between four players, using hands instead of cue sticks. The goal is to shoot as many balls as possible into the diagonally opposing corner pocket you are standing behind. The shooting is done taking turns and rotating counter clockwise. When misses on the pocket occur, the ball is open game to be stolen and pocketed in the new opposing pocket during the new owners turn. Ties are decided by lagging with the hands, and the winner of one game is the first to shoot in the next.
A set of paired balls in the game of cribbage pool that have a number value which combined equal 15. For example, the 8 ball and the 7 ball added together equal 15 and thus constitute one cribbage if pocketed in succession.
A pool table where two shims have been placed on the sides of each pocket (in the jaws beneath the cloth), making the pockets "tighter" (smaller). Such tables are "tougher" than unshimmed or single-shimmed tables.
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.
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.
This is English that turns into running action after contact with the object ball. This will open up the angle on a bank.
Same as position. "She got good shape for the next shot". See also position play, leave.
Often times a protective finish is applied to a cue stick after construction. A UV polyurethane is common, and this helps to protect the cue from fading and dings.