Definition of Heads up

An imaginary line dividing the table into two equal halves lengthwise. It intersects the head string, center string and foot string at the head spot, center spot and foot spot, respectively.

This describes balls that are not able to be made in a pocket, either because they are high up on the table, in a different pocket, or in a cluster that makes the shot difficult. This condition of being out of play obviously exists on different difficulty levels.

Same as side rail.

This is a shot in snooker where the cue ball follows a struck object into the pocket.

A break shot in which the rack (pack) is disturbed as little as possible within the bounds of a legal shot, in order to force the opponent to have to break it up further. A soft break is desirable in some games, such as straight pool, in which breaking is a disadvantage; and forbidden by the open break rules of other games such as nine-ball and eight-ball.

This is to have control on the cue ball in your shots.

A specific ball number followed by "out" refers to a handicap in nine-ball or other rotation games where the "spot" is all balls from that designated number to the money ball. To illustrate, the 6-out in a nine-ball game would allow the player getting weight to win by legally pocketing the 6, 7, 8 or 9 balls.
Short for run out, especially as a noun: "That was a nice out."

When the cue ball is tucked behind the corner of a pocket, therefore not allowing a direct shot at the object ball without it bouncing of the corner of the rail.

The effect of shooting regulation-weight object balls with an old-fashioned over-weight bar table cue ball, such that the cue ball moves forward to occupy (sometimes only temporarily), or go beyond, the original position of the object ball, even on a draw or stop shot, because the mass of the cue ball exceeds that of the object ball. Players who understand smash-through well can use it intentionally for position play, such as to nudge other object balls nearby the target ball. Smash-through also makes it dangerous in bar pool (when equipped with such a cue ball) to pocket straight-on ducks with a stop shot instead of by cheating the pocket because of the likelihood of scratching the cue ball.

Derived from "sitting duck", usually referring to an object ball sitting close to a pocket or so positioned that is virtually impossible to miss. Same as hanger (US, colloquial), sitter (UK).

The 'Lady Jane Grey' is a rarely used term to describe a shot in the game of snooker. The cue ball is baulk side of the spotted black after potting a red ball. The black is powerfully potted into a top corner pocket and the cue ball bounces off the top cushion into the red balls, moving them into space, thus allowing the continuation of a break. Named after Lady Jane Grey, the 16th Century Queen of England, possibly because the speed the cue ball must be hit matches the speed with which she was deposed from the throne.

The forward rotation of the cue ball that results from a follow shot. Also known as top spin or top, follow is applied to the cue ball by hitting it above its equator, causing it to spin more rapidly in the direction of travel than it would simply by rolling on the cloth from a center-ball hit. Follow speeds the cue ball up, and widens both the carom angle after contact with an object ball, and angle of reflection off a cushion.

A defensive action taken when a player either has no "makeable" or "high percentage" shot or chooses to leave his opponent in a difficult situation. It is a legal shot and is not considered to be dirty pool. A safety must still conform with the rule concerning hitting the correct ball first and striking a rail afterwards. If a correct ball is accidentally pocketed while playing safe, the shooter must continue to shoot.

A tournament format in which each contestant plays each of the other contestants at least once. In typical league team play, round robin format means that each member of the home team plays each member of the visiting team once. This format is used by BCAPL, VNEA and many other leagues.

This is a bank in which the object ball hit will cross the path of the cue ball on the way to its destination.

Noun:
1.In pool games such as nine-ball, a specific handicap given (e.g., "what spot will you give me?").
2.In snooker, any of the six designated points on the table on which a colour ball is replaced after it has left the playing surface (usually after it has been potted).
3.An (often unmarked) point on the table, at the intersection of two strings. See foot spot, head spot, center spot for examples.
4.In UK eight ball, (when not playing with a reds-and-yellows colour ball set) any of the group of seven balls, other than the 8, that are a solid colour with just a circled number on the surface. In the US, these balls are usually referred to as solids or more colloquially as lows, littles or smalls, while British terms include dots and unders. Contrast stripes.
5.Alternate name for a table's diamonds.

Verb:
1.In pool, return an illegally pocketed object ball to the table by placement on the foot spot or as near to it as possible without moving other balls (in ways that may differ from ruleset to ruleset).
2.In snooker, to return a colour ball to its designated spot on the table. Also called re-spot.
3.In nine-ball, the giving of a handicap to the opponent where they can also win by making a ball or balls other than the 9 ball (e.g. "she spotted me the seven ball").
4.In eight-ball, one-pocket and straight pool, the giving of a handicap to the opponent where they have to make fewer balls than their opponent does.
5.In some variants of pool, to place the cue ball on the head spot or as near to it as possible inside the kitchen/baulk, after the opponent has scratched.

(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.

This is the way a ball rolls when impeded by something on the table or a blemish in the cloth, often times regular players will remember certain rolls and play to them.

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.

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.

Hitting the object ball with too large of a cut angle; hitting the object ball too thin. It is a well-known maxim that overcutting is preferable to undercutting in many situations, as is more often leaves the table in a disadvantageous position on the miss than does an undercut. See also professional side of the pocket.

This is a special shaped leather or plastic bottle that is used on the table during play in special pocket games.

An illegal shot (foul) in which the cue stick's tip contacts the cue ball twice during a single stroke. Double hits often occur when a player shoots the cue ball when it is very close to an object ball or cushion, because it is difficult to move the cue stick away quickly enough after the cue ball rebounds from the cushion or object ball.

This is a ball that is positioned near your pocket that can be used to kiss off of when sinking another object ball.