Definition of round

A multi-game division of a match, as used in some league and tournament formats. For example, in a match between 2 teams of 5 players each, a 25-game match might be divided into 5 rounds of 5 games each, in which the roster of one team moves one line down at the beginning of each round, such that by the end of the match every player on team A has played every player on team B in round robin fashion.
A level of competition elimination in a tournament, such as the quarterfinal round, semifinal round and final round.

24 Random Essential Billiards Terms

The angle from which a ball rebounds from a rail, as measured from the perpendicular to the rail.
Often times a protective finish is applied to a cue stick after construction. A UV polyurethane is common, and this helps to protect the cue from fading and dings.
Asian Pocket Billiard Union. The APBU is a member of the WPA.
A barrel is how much money per game a player is betting. As in, "I have ten barrels at $20 a game".
Side spin on a cue ball on the opposite side of the direction of the cut angle to be played (right-hand english when cutting an object ball to the left, and vice versa). In addition to affecting cue ball position, outside english can be used to decrease throw.
Same as centre pocket.
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.
"Pocket billiards," or a game in which balls are shot into pockets.
Same as suit, predominantly in British terminology, i.e., in eight-ball either of the set of seven balls (reds or yellows) that must be cleared before potting the black. Generally used in the generic, especially in rulesets or articles, rather than colloquially by players.
When a particular ball is given as a handicap in nine-ball, designating that ball in turn means that it must be made in rotation, when it is the lowest numerical ball remaining on the table, and cannot be made to garner a win earlier in the game by way of a combination, carom or any other shot. For example, if a player is spotted the 8 ball, he only wins by making that ball after balls 1 through 7 have been cleared from the table.
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."
This is a kind of cue made of four pieces of wood, the butt sleeve, the points, the handle, and the forearm, with each piece pinned, doweled, and glued together.
In blackball, a penalty conceded by a player after a fault. The incoming opponent is then allowed to miss twice before the faulting player is allowed another visit. Many local rules state the in-hand from the "D" or baulk (or if the opponent potted the cue ball, from anywhere) nature of the second shot is lost if a ball is potted on the first shot, that it is lost if the ball potted in the first shot was that player's last coloured ball (object ball in their group), and/or that there is only ever one shot on the black after a fault.
A chiefly British term for a set of mechanical bridges. British-style rests differ from most American-style rake bridges in shape, and take several forms: the cross, the spider and the swan (or goose neck), as well as the rarer and often unsanctioned hook. When used unqualified, the word usually refers to the cross. Rests are used in snooker, English billiards, and blackball.
Same as cheating the pocket. Principally used in snooker.
Sometimes called a snake shot. A carom billiards shot, common in three-cushion billiards, where the cue ball is shot with reverse english at a relatively shallow angle down the rail, and spins backwards off the adjacent rail back into the first rail.
This is when a ball is spotted because of a foul or a handicap.

1- This is a knowledgeable shot showing skill on the movement of the cue ball.

2- This is an experienced one pocket pool player that shows extraordinary skill at coordinating the cue balls and object balls for safety plays.

This is to win a game by pocketing enough balls before you opponent.
A point bead on a scoring string.
Same as triple.
Also lows, low, low ones. In eight-ball, to be shooting the solid suit (group) of balls (1 through 7); "you're low, remember", "you're low balls" or "I've got the lows." Compare solids, reds, little, spots, dots, unders; contrast high.
This is when, after playing an opponent for a while you both break even as far as money exchange, and the only person to get paid is the house for use of their table.
This is a game played with the same balls and similar scoring methods of carom, but with pockets on the table, and more scoring opportunities awarded when certain balls are sunk in combination.