Definition of Tangent line

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'.

This is another name for One Pocket pool.

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.

A British term for a pot that requires very fine contact between cue ball and object ball. See also feather.

A player's auction at a pool tournament. Each player is called and players and spectators bid on the player. The highest bidder(s) pays their bid to the calcutta, and by doing so invest in that player's success. If a player wins or places in the tournament, those who "bought" the player receive a percentage of the total calcutta payout, usually tracking the percentage payout of the tournament prize fund. Typically, players have the option of purchasing half of themselves when the high bid is won by a third party. Like english and scotch doubles, usually not capitalized.

Confederation Panamerica of Billiards

A directional pile created by the short fuzzy ends of fibers on the surface of cloth projecting upward from the lie and which create a favorable and unfavorable direction for rolling balls. The convention in most billiards games in which directional nap cloth is used is to brush the cloth along the table in the same direction of the nap, usually from the end that a player breaks. In snooker and UK eight-ball especially, this creates the effect of creep in the direction of the nap, the most-affected shot being a slow roll into a center pocket against the nap. It is commonly referred to in the fuller term "nap of the cloth." When nap is used in relation to woven cloths that have no directional pile, such as those typically used in the U.S. for pool tables, the term simply refers to the fuzziness of the cloth.

This is a kind of cue made of only two pieces of wood, and joined together using an advanced adhesive along the points of the cue. This connection gives the cue a flawless look and a fluid feel when shooting.

A shot, especially common in straight pool and in some variants of blackball (but not WEPF/EPA rules), in which a player intentionally commits a foul with the object in mind of either leaving the opponent with little chance of running out or simply to avoid shooting where no good shot is presented and to do anything else would give the opponent an advantage. It is often referred to in straight pool as a "back scratch."

This a shot that hits the object ball at the nine ball to see if you can get lucky by sinking the nine ball in any pocket. (also see Cheese the Nine and Rolling the Cheese).

The point on the table surface over which the apex ball of a rack is centered (in most games). It is the point half the distance between the long rails' second diamonds from the end of the racking end of the table. The foot spot is the intersection of the foot string and the long string, and is typically marked with a cloth or paper decal on pool tables.

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.

When a player is playing flawlessly, just "cannot miss" and the game seems effortless.

An instance of contact between balls, usually used in the context of describing an object ball contacting another object ball (e.g. "the two ball kissed off the twelve ball"), or in snooker the cue ball making contact with a ball after the initial contact with the object ball. If the player's intention was to cause two object balls to kiss (e.g. to pocket a shot ball after a ricochet off a stationary one), it is often called a kiss shot.

Term for object balls in the game of Chicago that are each assigned as having a set money value; typically the 5, 8, 10, 13 and 15. In games where multiple balls must be pocketed in succession to score a point, such as cribbage pool or thirty-ball, when the last ball necessary to score has been potted, the points given is referred to as a way.

Hitting the object ball with not enough of a cut angle; hitting the object ball too full or "fat". It is a well-known maxim that overcutting is preferable to undercutting.

Also shortstop, short-stop. This is a player that is excellent at pool, but tends to fall short of number one. A shortstop is the best player relative to a particular scene. A second-tier professional who is not (yet) ready for World Championship competition. It can also be applied by extension to a player who is one of the best in a region but not quite good enough to consistently beat serious road players and tournament pros. The term was borrowed from baseball.

This is to watch a match with such intensity that there is worry, usually because of a wager on the game.

Chiefly British: bank shot played up and down the longer length of the table off a short rail and into a corner pocket, as opposed to the more common bank across the short length into a center pocket or corner.

A shot that only a novice or fool would take. Usually because it is a guaranteed scratch or other foul, or because it has a low percentage of being pocketed and is likely to leave the opponent in good position.

The desired angle that must be created between the path of the cue ball and the path of the object ball upon contact to pot the object ball. It is usually measured to the center of the pocket. See also aiming line.

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 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.

In snooker, the colour ball worth 5 points, whose spot is at the center of the table.