Definition of Hazard

A low hit on the cue ball (but not as low as normal draw), often used to change the cue ball's angle of deflection off the object ball.

Either of the two shorter rails of a billiards or pocket billiards table.

This is a type of shot where the cue ball goes off the rail before it heads to contact the object ball, thus giving the cue better position in some shots.

The person in charge of the game whose primary role is to ensure adherence by both players to the appropriate rules of the game being played. Other duties of the referee include racking each frame, re-spotting balls during the course of a game, maintaining the equipment associated with the table (e.g. keeping the balls clean), controlling the crowd and, if necessary, controlling the players. Formerly sometimes referred to as the umpire.

In a tournament, to place high enough to receive a payout. E.g., in a tournament that pays from 1st down to 5th places, to be at least 5th place is to be in the money.

The collar is the portion of the joint that is attached to the top of the forearm. This is often stainless steel, wood, ivory, or molded phenolic resin, but in any case, made out of a solid material. This portion of the cue is glued on and threaded to reinforce the pin at the end of the shaft, and to offer a stabilized shot out of its solid construction.

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 a player who has the ability to make difficult shots in one pocket, because they are likely proficient at other pool games first.

This can be a shot where the best option for you is to sink a ball in you opponents pocket in the game of one pocket. This can also refer to the act of offering an opponent a ball adjustment to even the playing field.

Billiard Congress of America. The official governing body for pocket billiards in the United States.

This is another name for One Pocket pool.

The break box is a zone in the "kitchen" of the head (British: bottom) of the table, from which the break shot must be taken with the cue ball,

One of the two pockets one either side of a pool table halfway up the long rails. They are cut shallower than corner pockets because they have a 180 degree aperture, instead of 90 degrees. In the UK the term centre pocket or middle pocket are preferred.

A game of pool played on a table shaped like a rectangle, with or without pockets.

Playing an opponent for money who has no chance of winning based on disparity of skill levels. The term robbed is also sometimes used humorously in exclamations when a shot that looks like it would work did not, as in "Oh! You got robbed on that one!"

Toward the foot of the table.

In nine-ball, especially in the UK, a break shot that pots the 9 ball without fouling, in which case the player wins in one shot. See also on the break/snap.

A term applied especially in snooker for a type of double off three cushions, e.g. around the baulk colours and into a centre pocket. Such a shot is very difficult to make and would not normally be played as anything more than a shot for nothing.

Failure to hit an object ball at all with the cue ball. In most sets of rules, this is a foul like any other. However, in some variants of bar pool a table scratch while shooting for the 8 ball is a loss of game where other more minor fouls might not be, as is scratching on the 8 ball (neither result in a loss of game in most professional rules).
By way of drift from the above definition, the term is also applied by many league players to the foul in more standardized rules of failing to drive a (any) ball to a cushion, or to pocket a legal object ball, after the cue ball's initial contact with an object ball.
By way of entirely different derivation ("scratch off the table"), it can also mean knocking the cue ball (or more loosely, any ball) completely off the table.

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

An area defined on a billiard table, in games such as pool, snooker, English billiards and bagatelle, by a single balkline (drawn or imaginary) that runs across the table near the head (bottom) end; exactly where depends upon table type and size. This balk is where the cue ball is placed in lagging for lead, for making the opening break shot, and sometimes for other purposes, depending upon the game.

This refers to the cluster of balls remaining in a similar position to where they were within the break

Also goose neck rest. Same as swan.

Also pills, tally balls and shake balls. Small, round markers typically numbered 1 through 15 or 16, which are placed in a bottle for various random assignment purposes, such as in a tournament roster, to assign order of play in a multiplayer game, or to assign particular balls to players in games such as kelly pool.