Definition of Pile

This the area behind the pocket points before the pocket. The ball can get behind here and rest waiting to be pocketed, or the cue ball can get corner hooked in this location. Different tables feature a smaller or larger area here which can make these situations more or less achievable.

Describing a ball that is safe because it is in close proximity to one or more other balls, and would need to be developed before it becomes pottable.

Refers to a person gambling when he has no money. As in, "That jerk can't pay up, he was shooting air barrels the whole time".

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

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.

Any ball that may be legally struck by the cue ball.

This is to direct the cue ball by barely contacting an object ball.

A geometric form, usually aluminum, wooden or plastic, used to assist in setting up balls in games like eight-ball, nine-ball, and snooker. The rack allows for more consistently tight grouping of balls, which is necessary for a successful break shot. In most games a triangle-shaped rack capable of holding fifteen balls can be employed, even if the game calls for racking less than a full ball set, such as in the game of nine-ball. For further information, see the Rack (billiards) main article.
In some games, refers to a single frame.

In snooker, the cushion opposite the top cushion and bounded by the yellow and green pockets (i.e. same as bottom cushion).

This is a kind of cue made of four pieces of wood, the butt sleeve, the points, the handle, and the forearm, with each piece pinned, doweled, and glued together.

Four-ball is a carom billiards game. The game is played on a pocketless table with four balls, usually one light red, one dark red, and two whites (or just two reds and two whites). Each player is assigned one of the white balls as his own cue ball. A point is scored when a shooter caroms on any two other balls. Two points are scored when the player caroms on each of the three other balls.

Same as angle of reflection.

This is the act of disturbing you opponents good looking balls in the hope that they might move over and help you out in the game of one pocket.

Same as gapper

This is the red colored object ball in carom games.
In snooker, any of the 15 balls worth 1 point each that can be potted in any order. During the course of a break a player must first pot a red followed by a colour, and then a red and colour, etc., until the reds run out and then the re-spotted six colours must be cleared in their order. Potting more than one red in a single shot is not a foul - the player simply gets a point for each red potted.
In blackball, one of two groups of seven object balls that must be potted before the black. Reds are spotted before yellows, if balls from both group must be spotted at the same time. Compare stripes; contrast yellow ball.
In carom billiards, the object ball that is neither player's cue ball.

A material, usually leather, placed on the end of a cue stick that comes in contact with the cue ball.

A two-piece cue constructed to resemble a house cue, with a near-invisible wood-to-wood joint. The subterfuge often enables a hustler to temporarily fool unsuspecting fish into thinking that he or she is an unskilled banger with no regard for finesse or equipment quality. Many league players also use cheap but solid sneaky petes as their break cues.

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.

This is another name for One Pocket pool.

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.

This is when a mistake is made in the shot and the resulting contact between balls forces you to miss the shot.

Any system for banking or kicking balls multiple rails which uses table diamonds as aiming references.

The ornamentation on a cue, between the wrap and the joint, is often made by inlaying exotic materials into the wood so the inlays form points. The value of a cue is often based on the number points.

A break shot in which the object is to leave the incoming player with no shot or a very difficult shot, such as is normally employed in the opening break of straight pool. Cf. open break.