Definition of lost their stroke

A player who was playing very well but suddenly starts playing badly. e.g. "He was making everything on every shot, then lost his stroke and couldn't hit anything, costing him the match."

24 Random Essential Billiards Terms

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).
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.
The angle at which a ball approaches a rail, as measured from the perpendicular to the rail.
In one pocket pool this means that you change your play based on where the count is during the game. If you are ahead you might choose more conservative shots, and if you are behind you could choose more aggressive shots.
In snooker and other British usages, a break of 50-99 points (100 points or more being called a century), which involves potting at least 12 consecutive balls (i.e. the last 3 reds with at least 2 blacks and a pink, followed by all the colours).
Chiefly American, and largely obsolete: Same as referee.
Also money-added. Said of a tournament in which the pot of money to pay out to the winner(s) contains sponsor monies in addition to competitor entry fees. Often used as an adjective: "a money-added event".
In snooker, the cushion opposite the top cushion and bounded by the yellow and green pockets (i.e. same as bottom cushion).
An intentionally amateurish stroke to disguise one's ability to play.
This is a ball that is left in a position that allows an easy shot, while time is spent working with other balls to better your position in the game.
A Carom game with lines drawn to form rectangles that restrict play and reduce the potential for high runs.
A bank shot is when the shooter (player) bounces the cue ball or the object ball (after it is hit by the cue ball) off a rail in an attempt to make the shot. A successful bank shot will result in sinking the object ball or a defense that will make it very difficult for the opponent to attempt their shot.
This is what is brought to the table if you are playing at your best potential.
Also slop shot. A luck shot. Compare fish, fluke and Lorengo; contrast mark and call. Also sloppy. Descriptive of any game where the rules have been varied to allow luck shots not normally allowed or where no foul rules apply.
Chiefly British: The cushion on the top rail. Compare foot cushion; contrast bottom cushion.
A ball that is easily made from many positions on the table but which is left untouched while the rack is played, so that in the event the player gets out of position, the shooter has an insurance shot. Typically an insurance ball will be in or near the jaws of a pocket.
Sometimes interchangeable with scratch, though the latter is often used only to refer to the foul of pocketing the cue ball. A violation of a particular game's rules for which a set penalty is imposed.
This is placed on a ball by hitting it slightly below center. This action makes the ball travel in a motion against its originally hit direction.
Describing a difficult pot: "the awkward cueing makes this shot missable."
Also known as 14.1 continuous pool. This game is played on a pocketed table with the fifteen object balls and a cue ball. Every shot must begin with a call, and if made, you get to continue calling shots. The idea is to reach a predetermined score before your opponent. When all but one ball remains, the rack is started over without the apex ball in position, and the last shot is called in such a way as to break the new rack and continue play.
The pocket in snooker that is closest to the green spot.
This is the running score of a player during his inning of play. The sum of the continuously scored points, or where the player stands in the run on the table.
This is a toned down masse shot. The cue is elevated a little and will curve a little in the direction the spin is applied. This is used to sneak around difficult shots.
A shooter's body position and posture during a shot.