Definition of shark

1- Short for "pool shark", poolshark (US); sharp, "pool sharp" (British)

2- Verb: To perform some act or make some utterance with the intent to distract, irritate or intimidate the opponent so that they do not perform well, miss a shot, etc. Most league and tournament rules forbid blatant sharking, as a form of unsportsmanlike conduct, but it is very common in bar pool.
Noun: Another term for hustler.
Noun: A very good player. This usage is common among non-players who often intend it as a compliment and are not aware of its derogatory senses .

24 Random Essential Billiards Terms

Chiefly American: The half of the table in which the object balls are racked (in games in which racked balls are used). This usage is conceptually opposite that in British English, where this end of the table is called the top. Contrast head.
The game of snooker. This is a very demanding game that isn't played as often in the U.S. as it is in other countries. The table needed is slightly larger, and there are 15 red object balls needed in addition to six color balls. After the balls are set up according to the rules, play resumes in turns with points scored as one on each red ball, and as is denoted with each other colored ball sunk. This is a challenging game that demands skill and excellent execution.
To leave the opponent (accidentally or by means of a safety) so that a certain shot on a preferred object ball cannot be played directly in a straight line by normal cueing. It most commonly means that the object ball cannot be hit, because it is hidden by another ball or, more rarely, the knuckle of a pocket (see corner-hooked). It can also refer to the potting angle or another significant point of contact on the object ball, blocking an otherwise more straightforward shot, even if an edge can be seen. A common related adjective describing a player in this situation is snookered. Also known as "to hook", for which the corresponding adjective "hooked" is also common. See also free ball.
An instance of this situation (e.g. "she's put him in a difficult snooker"). A player can choose a range of shots to get out of a snooker; usually a kick shot will be implemented but semi-massés are often preferred, and in games where it is not a foul, jump shots may be employed that often yield good results for skilled players. "Snooker" is used loosely (when used at all; "hook" is favored) in the US, but has very specific definitions and subtypes (such as the total snooker) in blackball.
The inside walls of a pocket billiards table's pockets.
To intentionally hide one's "speed"; "he's on the stall."
To intentionally play slowly so as to irritate one's opponent. This form of sharking has been eliminated from many tournaments with a shot clock, and from many leagues with time-limit rules.
Any mechanical aid that serves to extend the length of the player's cue, normally added to the end of the butt either by clipping around the end or screwing into the base. Though extensions are used for pool, it is more common in snooker because of the significantly larger table size.
In a tournament where players get limited time to make their shots (common in televised matches), an extension is extra time granted before making a shot; players have a limited number of extensions in each frame.
A ball positioned near a pocket so that a particularly positioned object ball shot at that pocket will likely go in off it, even if aimed so imperfectly that if the warrior was absent, the shot would likely result in a miss. Usually arises when a ball is being banked to a pocket.
To take one's two-piece cue stick apart. When done before a game's conclusion, it often indicates that the game is conceded.
Same as foul
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 Rolling the Cheese and Cheese the Nine).
A pocket; usually used in disgust when describing a scratch (e.g., "the cue ball's gone down the sewer").
A Carom game with lines drawn to form rectangles that restrict play and reduce the potential for high runs.
To bungle a shot in a manner that leaves the table in such a fortuitous position for the opponent that there is a strong likelihood of losing the game or match. Contrast sell out.
A fast paced offensive game similar to 9-ball but only using balls numbered 1 through 7.
Pocketing the 7-ball wins the game. Under the current pro rules of 7-ball, any missed shot gives your opponent ball-in-hand.
A ball hanging over the edge of a pocket.
This is a bank in one pocket pool that is sitting at an angle that makes it unsafe to play.
Also piquet. Either a massé shot with no english, or a shot in which the cue stick is steeply angled, but not held quite as vertical as it is in full massé.
This piece of armament keeps the butt of your cue safe from coincidental contact with the floor or other damaging incidents. It is usually made of a rubber composite or other durable or flexible material to absorb impact in the case of a collision.
A pejorative term for an improper rack in which the balls are not properly in contact with their neighbors, often resulting in a poor spread on the break.
This shot is a minimally calculated distressed shot which makes it evident to the opponent you no longer have any hope to winning the game.
To indicate where something is to be done. To "mark the pocket" means to indicate which pocket you intend to sink an object ball.
Chiefly British: The half of the table from which the break shot is taken. This usage is conceptually opposite that in North America, where this end of the table is called the head.
The surface of the table used for play (often made with slate).
One-on-one game play.
Either of the two shorter rails of a billiards or pocket billiards table.