Definition of Rail

In the eight-ball game variant blackball, also known as eight-ball pool, a differently colored but otherwise identical replacement for the red group (i.e., what would be the solids in an American-style pool ball set).

The imaginary line drawn perpendicular to the impact line between the cue ball and an object ball. The cue ball will travel along this line after impact with an object ball if it has no vertical spin on it (is sliding) at the moment of impact on a non-center-to-center collision. See also stun shot.

(Chiefly U.S.) Side spin (english) placed on a same side of the cue ball as the direction in which the object ball is being cut (left-hand english when cutting a ball to the left, and vice versa). In addition to affecting cue ball position, inside english can increase throw.

In the carom games, any shot where the end result is all the balls near each other; ideally, in position for the start of a nurse on the next stroke.

When the cue ball is tucked behind the corner of a pocket or behind other object balls against a rail, therefore not allowing a direct shot at the object ball without the cue bouncing off the corner of the rail.
A term also used to mean when the object ball you must hit next is hidden behind other balls against a rail and you are not able to get a clean hit (without hitting other object balls first) on it. e.g. "You hooked me".

The sides of a table's frame upon which the elastic cushions are mounted. May also be used interchangeably with cushion.

A unit of scoring, in games such as snooker and straight pool with numerical scoring.
A unit of scoring, in team matches in leagues that use numerical scoring instead of simple game/frame win vs. loss ratios.
Another term for knuckle / tittie.

This is the raised portion on the side of the table; the cushions are essentially rubber bumpers covered in the table cloth.

When you have completed a shot by pocketing a ball into a pocket.

A player skilled at very thin cut shots, and shots in which a ball must pass cleanly through a very narrow space (such as the cue ball between two of the opponent's object balls with barely enough room) to avoid a foul and/or to pocket a ball. Such shots may be referred to as "surgery", "surgical shots", "surgical cuts", etc. (chiefly US, colloquial). See also feather (US) or snick (UK).

This word is used as slang to define a player as amateur or recreational.

"Pocket billiards," or a game in which balls are shot into pockets.

To shoot without taking enough warm-up strokes to properly aim and feel out the stroke and speed to be applied. One-stroking is a common symptom of nervousness and a source of missed shots and failed position.

A very thin cut shot in which the cue ball just brushes the edge of an object ball. "Feather" by itself can be both noun and verb (e.g. "feathering the ball").

Also smalls, small ones, small balls. In eight-ball, to be shooting the solid suit (group) of balls (1 through 7); "you're the small one" or "I've got the smalls". Compare little, solids, reds, low, spots, dots, unders; contrast big.

This is the playing surface for billiards games. Consisting of 6 pockets, cushions on the side, and a felt layer covering the hard table portion, the length is usually twice as long as it is wide, but varies depending on the game at hand.

The pocket in snooker that is closest to the green spot.

This term refers to a foul in snooker golf.

(Chiefly British.) In snooker and blackball/eight-ball pool, an instance where the cue ball has been potted (pocketed) after contacting an object ball. It is a fault (foul) in most games. There is no equivalent (current) American term for this specific means of pocketing the white ball. Compare losing hazard, scratch.

Any shot where the cue ball stops immediately after hitting an object ball. Generally requires a full hit.

This is to execute a shot where the cue ball is controlled perfectly and stops where you want it to exactly.

This is the way your hand is configured to support the shaft of the cue during a shot.

A rack in the form of an equilateral triangle. There are different sizes of triangles for racking different games (which use different ball sizes and numbers of balls), including the fifteen ball racks for snooker and various pool games such as eight-ball and blackball. A larger triangle is used for the twenty-one ball rack for baseball pocket billiards). The smallest triangle rack is employed in three-ball (see illustration at that article) but is not strictly necessary, as the front of a larger rack can be used, or the balls can be arranged by hand.
The object balls in triangular formation, before the break shot, after being racked. See also pyramid.

A highly abrasive tip tool used to shape an unreasonably flat new cue tip, or misshapen old one, into a more usable, consistently curved profile, most commonly the curvature of a nickel or dime (or equivalently sized non-US/Canadian coin) for larger and smaller pool tips, respectively. Similar to a scuffer, but deeper and rougher.