Glossary of Chess

Pairing

The assignment of opponents in a tournament. Pairing is made more difficult in chess because of the need to try to give each player an equal number of games playing white and black and to try to not assign a player the same color in too many consecutive games. The most common pairing methods used in chess tournaments are round-robin and the Swiss system.

Passive

A piece that is able to move to or control relatively few squares, also referred to as an inactive piece. See active.

Passive sacrifice

When a piece is sacrificed by moving a different piece, leaving the sacrificed piece under attack.

Passed pawn

A pawn that has no pawn of the opposite color on its file or on any adjacent files on its way to queening.

Passer

A passed pawn.

Patzer

A weak chess player. (German: patzen, to bungle.)

Pawn

see pawn

Pawn and move

A type of odds game, common in the 18th and 19th centuries, in which the superior player plays Black and begins the game with one of his pawns, usually the king bishop pawn, removed from the board.

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1									1
	a	b	c	d	e	f	g	h

White has a large pawn centre

Pawn centre

A player has a pawn centre when he has several pawns in the centre. By extension, pawns on the squares adjacent to the centre may also be considered as part of the pawn centre. Having an ample pawn centre as the one on the diagram at right was considered a huge advantage until the hypermodernist school nuanced this judgment. See King's Indian Defence, Four Pawns Attack for an example of an opening leading to an extended pawn centre.

	a	b	c	d	e	f	g	h
8									8
7									7
6									6
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3									3
2									2
1									1
	a	b	c	d	e	f	g	h

Pawn chains in the French Defence

Pawn chain

A locked diagonal formation of pawns, each one supported by a friendly pawn diagonally behind and blocked by an enemy pawn directly ahead. Nimzowitsch considered pawn chains extensively, and recommended attacking the enemy pawn chain at its base. See pawn structure.

Pawn island

A group of pawns of one color on consecutive files with no other pawns of the same color on any adjacent files. A pawn island consisting of one pawn is called an isolated pawn.

Pawn storm

An attacking technique where a group of pawns on one wing is advanced to break up the defence.

Pawn structure

The placement of the pawns is known as the pawn structure. As pawns are the least mobile of the pieces and the only pieces unable to move backwards, the position of the pawns greatly influences the character of the game.

PCA (Professional Chess Association)

The Professional Chess Association (PCA) was a rival organisation to FIDE, the international chess organization. The PCA was created in 1993 by Garry Kasparov and Nigel Short for the marketing and organization of their chess world championship. The PCA lost its main sponsor, Intel, in 1996 and folded soon after.

Performance rating

A number reflecting the approximate rating level at which a player performed in a particular tournament or match. It is often calculated by adding together the player's performances in each individual game, using the opponent's rating for a draw, adding 400 points to the opponent's rating for a win, and subtracting 400 points from the opponent's rating for a loss, then dividing by the total number of games. For example, a player who beat a 2400-rated player, lost to a 2600, drew a 2500, and beat a 2300, would have a performance rating of 2550 (2800 + 2200 + 2500 + 2700, divided by four).

Perpetual check

A draw forced by one player putting the opponent's king in a potentially endless series of checks.

Philidor position

Usually refers to an important chess endgame which illustrates a drawing technique when the defender has a king and rook versus a king, rook, and pawn. It is also known as the third rank defence, because of the importance of the rook on the third rank cutting off the opposing king. It was analyzed by Philidor in 1777. (Also see rook and pawn versus rook endgame.)

Piece

This term can mean either any chess piece including pawns (as in the touched piece rule), or a minor piece (as in "I hung a piece"), depending on context. It can also mean a major or minor piece, as in "White needs to get some pieces to the kingside."

Pin

When a piece can not move (either legally or advisedly) because doing so would expose a valuable piece, usually the king or queen, to attack. Pins against the king are called absolute because it is then illegal to move the pinned piece.

Plan

A strategy used by a chess player to make optimal use of his advantages in a specific position while minimizing the impact of his positional disadvantages.

Playable

Said of an opening or move that gives the person playing it a tenable position, e.g. "Petroff's Defense is playable." or (after 1.e4 e5 2.Bc4 Nf6 3.Nc3 Nxe4 4.Nxe4) "4...d5 is the only playable move."

Ply

Term mainly used in computer chess to denote one play of either white or black. Thus equal to half a move.

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7									7
6									6
5									5
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3									3
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1									1
	a	b	c	d	e	f	g	h

Black has accepted the "poisoned" b2-pawn with 8...Qxb2

Poisoned Pawn Variation

An unprotected pawn which, if captured, causes positional problems or material loss. It is also a variation of the Najdorf Variation of the Sicilian Defence, where some players call White's pawn on b2 a poisoned pawn since it is dangerous for Black to capture it.

Portable Game Notation (PGN)

This is a popular computer-processible ASCII format for recording chess games (both the moves and related data).

Positional play

Play dominated by long-term maneuvering for advantage rather than by short-term attacks and threats, and requiring judgment more than extensive calculation of variations, as distinguished from tactics.

Positional player

A player who specializes in positional play, as distinguished from a tactician.

Post-mortem

Analysis of a game after it has concluded, typically conducted by one or both players and sometimes spectators (kibitzers) as well.

Prepared variation

A well-analyzed novelty in the opening which is not published but first used against an opponent in competitive play.

Promotion

Advancing a pawn to the eighth rank, converting it to a queen, rook, bishop or knight. Promotion to a piece other than a queen is called underpromotion.

Prophylaxis