Chess Glossary
 
Abandon: To give up all concern in a game or formally stating a voluntary decision to give up a game because of discouragement, weariness, distaste etc.

Accelerated Pairing Systems: Swiss system variant used to reduce the number of tournament leaders in as few rounds as is practical. The Swiss system lists the competitors based on strength, then cuts the list in the middle and pairs the highest player in each group against each other and so forth. In the ‘Accelerated System’, the field is divided into 4 groups with the top player of group-01 paired against the top player of group-02 and the top player of group-03 against the top player of group-4 and so forth.
Activity: The quality of a Chess position that describes mobility or freedom of movement for pieces. An active piece is more likely to have a positive influence in the outcome of a game than an inactive piece (a cramped, blocked, or undeveloped piece). Active pieces is one key quality in assessing a Chess position.
Adjournment: An unfinished game may be adjourned and continued at a later time/date. The player to make the next move on the board is required to write the next move on a piece of paper which is given to the referee. This is called a ‘sealed move’. When the game recommences this move must be the next move played on the chessboard. The adjournment rule was first introduced in 1878 in Paris.
Adjudication: In amateur events, games not finished within a specified time period, sometimes are adjudicated by a strong player who determines the outcome of the game. This practice has fallen out of fashion and has been replaced by "sudden death".
Advanced Pawn: This term describes a Pawn which has passed the central line of the chessboard which is between the fourth and fifth ranks.
Advantage: A superiority of position, usually based on force, time, space or Pawn structure. A player whose position is considered objectively better is said to have the advantage. A judgement of an advantage must consider complex criteria such as material (more pieces or Pawns), space (more room to maneuver), activity (more influence of pieces), King safety (one side has a safer King than the other), or other weaknesses (backward Pawn, etc.).
Algebraic notation: Same as Chess notation or simply notation. It is a combination of letters and numbers (a to h and 1 to 8) which denotes the 64 squares of the board. Algebraic notation has become the standard.
Ajeeb: A life-size figure which was operated by many Chess and Checker players including Constant Ferdinand Burille. Built by Charles Hopper in 1865. It played 900+ games and lost only three times and never lost a checker game.
Analysis: The calculation and detailed study of a series of moves based on a particular position in a game.
Annotation: Written comments about a position or a game, it can be narrative, Chess notation or both.
Announced Mate: A former practice to loudly proclaim a Checkmate. It is no longer permitted by the rules of Chess.
Arbiter: Chess has Arbiters for the enforcement of the rules.
Attack: An aggressive action during a game or to threaten to capture a piece or Pawn. Minority Attack: an attack of minor pieces against a majority of minor pieces of the opponent with the objective of creating a weakness in his position.


B: Abbreviation for Bishop.
Back rank mate: A checkmate made by a Queen or Rook along the 8th rank where the opponent's King is blocked in by its own Pawns.
Backward Pawn: A Pawn that has trailed behind and is no longer supported by other Pawns. A backward Pawn is consider a fundamental weakness in a Chess position because it can be attacked. Its defense requires pieces that are better employed in other plans. See also isolated Pawn.
Bad Bishop: Any ineffective Bishop. When a Bishop has little or no mobility because of being hemmed by Pawns positioned on squares of the same colour as the Bishop's square, it is said to be a "bad Bishop".
Battery: Doubling Rooks on a file or a Queen and a Bishop on a diagonal.
BCE: Basic Chess Endings.
BCF: British Chess Federation.
BCO: Batsford Chess Openings, the standard one volume reference book on opening strategy.
Bishop pair: Two Bishops vs. a Bishop and a Knight or two Knights. If both Bishops on the same side have survived late into a game of Chess, then their value is enhanced for two reasons. Together they can attack a piece on any color square. Their mobility is usually less restricted by Pawns late in the game. Therefore, a Bishop pair is a notable advantage.
Blindfold Chess: Games played without seeing the board. A Chess player who plays one or more opponents without sight of the board.
Blitz Chess: Rapid or lightning Chess games usually clocked in five or ten minutes.
Blockade: To stop an enemy Pawn by placing a piece or pieces directly in front of it. This term describes the situation where the advance of a Pawn is prevented by an opponent's piece directly in front of the frustrated Pawn.
Blocked: This term describes a piece whose mobility is limited by the physical presense of another piece often of the same color. Specific positions that involve blocked pieces include discovered check, double check, and blockade.
Blunder: A very bad move that loses material or initiative without any or little advantage. A mistake that overlooks a simple tactical response.
Book: The written body of high-level chess play. "Book" moves are standard. A book player memorizes openings and their variations, and goes to pieces if his opponent strays from the accepted line.
Book (moves): A pattern of moves expected to be played based on theoretical manuals by Chess players.
Breakthrough: An infiltration to the opponent's position.

 
Caissa: Goddess (muse) of Chess. The name is taken from a nymph in a poem composed by Sir William Jones in 1763. It is based on Vida’s ‘Scacchia ludus’, in which the nymph is referred to as ‘Scacchis’.
Calculate: To precisely work out a series of moves considering potential replies.
Calculation of variations: The working out of chains of moves without physically moving the pieces.
Candidate: A player who competes in the eliminating contest for the privilege to challenge the World Chess Champion. The Candidates’ matches are the final eliminating stage of the competition to decide the World Champion’s opponent in the title match.
Capture: The movement of a minor or major piece from the departure cell to the arrival cell and to capture a enemy piece in the process. To capture, a player must make a legal move that lands a piece on a cell containing an enemy piece. The captured enemy piece is taken from the board and removed from the game. To capture a MP/mp means to deprive your opponent (:A or :B) of the use of that MP/mp. The MP/mp has been taken and leaves the board.
Castling: A combined move of King and Rook permitted once for each side during a game. The King moves two squares to either side, and the Rook toward which it moves is placed on the square the King passed over. This is the only move in which the King moves more than one square at a time and in which more than one piece is moved.
Center: The four squares in the geometrical center of the board. The opening moves are meant to gain control of the center. The 'e'' and "d" files are the center files.
Cheapo: A clever tactical combination or trap usually made by a losing side to hold a draw or even a win.
Check: It refers to a King that is being attacked by an enemy piece. The King should move out of check, place another piece between the King and the attacking piece, or the attacking piece must be captured.
Checkmate: An attack against the opponent's King which the King cannot escape. Any position where a King cannot avoid capture. The objective end of a Chess game. When a player checkmates his enemy's King, he wins the game.
Clearance sacrifice: A move that sacrifices an obstructing piece to make way for a strong or better move.
Clock: Paired clocks used in all official tournaments and in club games. After a player moves, he depresses a lever that stops his clock and starts his opponent's. Each clock, therefore, registers only the elapsed time for one player. If a player exceeds the time limit set on his clock, a flag falls and he loses the game, even if he has a clear winning position.
Closed: A term used to describe a position where Pawns block the mobility of the pieces around some or all of the board. The opposite of an open position.
Closed file: A file blocked by both black and white Pawns.
Closed game: A game which the position is obstructed by blocking Pawns. Such a position favors Knights over Bishops since Pawns often block diagonals.
Combination: A series of moves or a tactical exploitation of a position which will force an immediate win by an overwhelming advantage in material or position. Most combinations sometimes start with a sacrifice of material.
Connected passed Pawns: Two or more passed Pawns of the same color on adjacent files which can protect themselves.
Connected Pawns: Pawns adjacent to one another.
Correspondence Chess: Chess game played by post or an electronic transmission.
Counter Gambit: A strategy in which a minor piece or Pawn is offered for sacrifice in response to an earlier gambit by the opponent.
Counter play: When the player who has been on the defensive starts his own aggressive action.
Cramped: The quality of a Chess position that inhibits mobility or freedom of movement for pieces behind Pawns of the same color. A cramped position lacks space. When a player's position is judged to be cramped, then that player has less freedom of maneuver than his opponent. A player that is cramped cannot switch the play from one side of the board to the other as quickly as his opponent. A cramped position is one key quality in assessing a Chess position.

 
Descriptive Notation: System of recording the moves of a Chess game based on the names of the pieces and places they occupy before the game begins. A move is given by the name of the piece or Pawn moving, followed by the square to which it moves. This notation is now almost completely replaced by algebraic notation.
Development: The process of moving pieces from their starting positions to new posts, from which they control a greater number of squares, have greater mobility or where they can better aid the player's plans.
Diagonal: A row of squares running obliquely across the board rather than up and down (a file) or side to side (a rank).
Discovered attack: A player, by moving a piece, uncovers an attack on an opponent's piece.
Discovered check: A discovered attack that involves checking your opponent's King by moving a piece so that the piece behind it can give check. This term describes an often powerful move where a line is opened allowing an otherwise blocked piece to give check to the enemy King. If the moving piece also gives check, then the move is described as a 'double check'.
Distance to conversion: A phrase used to describe the number of positions or plies in a tablebase between any given endgame position and a conversion of material. A conversion of material may be either a promotion or capture. Such conversions often indicate a major shift of endgame advantage.
Distance to mate: A phrase used to describe the number of positions or plies in a tablebase between any given endgame position and checkmate.
Distant opposition: Kings that oppose or are separated by more than one square, rank or file one another and still have the relation of opposition (e.g. Kings on g1 and g5) are said to be in "distant opposition." Kings in distant opposition can often maneuver to a more simple position of direct opposition but such maneuvering often requires careful calculation.
Double attack: An attack against two pieces or Pawns at the same time.
Double check: A powerful type of discovered attack, which checks the King with two pieces. The King is forced to move because no other means are available to extricate the King from this special type of check by two pieces simultaneously, thus frozen for at least one tempo or move.
Double lever: Kmoch's term for the situation where a Pawn may be captured by either of two Pawns, each in a different lever.
Double Pawns: Two Pawns of the same color lined up on a file. This doubling come about only as the result of a capture and generally considered a disadvantage because the Pawns cannot defend each other.
Double Rooks: Two Rooks of the same colour positioned on the same file or rank.
Draw: A tied game. A common result in a game of Chess when neither side wins or loses. A draw can result from a stalemate, the 50-move rule, the three-move repetition rule, if neither side has enough material to mate, by adjudication or by an agreement between the players.
Drawing chances: A The probability in any complex and roughly equal position that one or both sides may successfully draw a game of Chess. The game of Chess is extremely complex. Neither humans or machines can determine with certainty the outcome of a game when given a complex position. However, skilled and experienced players can often estimate the probability that one side can win, lose, or draw the game. Such an estimate is based on an understanding of sometimes subtle criteria such as board position, player skills, time pressure, and strategy both on the board and off.
Drawn position: Any Chess game position from which a draw must result from accurate play. Many complex drawn positions may still offer winning chances for one or both sides with alert play. The phrase "drawn position" is rarely used by experienced players to mean an artistically rendered, or randomly selected position. It is unknown whether the starting position is also a drawn position.
Duffer: Disparaging term to describe a very poor player.

 
ECO: Encylopedia of Chess Openings. A collection of texts detailing the moves of common Chess opening lines with commentary. Common opening lines are classified by a de facto standard ECO code such as B01 (Center Counter Game or Scandinavian Defense). A list of ECO codes in text and in PGN.
Edge: The "outside" squares of the Chess board, namely the first and eighth ranks and the a- and h- files.
Elo rating: The system by which players are rated. Devised by Professor Arpad Elo (1903 - 1993) of Milwaukee and adopted by FIDE in 1970. A beginner might have 900 rating, the average club player 1600, a state champion 2300, a Grandmaster above 2500, and world class players commonly achieve ratings above 2600. Some strong Grandmasters earn a rating in excess of 2700 and the World Champion 2800. This system in some form is used by most major Chess organizations.
Endgame: Also called the ending. This is the third and final state of the game after the opening and middlegame, characterized by the relatively few Chessmen on the board. The King is typically used more aggressively in the ending than in the opening or middle-game. One of the most common concerns in the endgame is promotion of Pawns.
En passant: From the French, "in passing." Abbreviated e.p. One Pawn can capture another e.p. if the capturing Pawn has reached the fifth rank and the captured Pawn is moved two squares forward on an adjacent file. The capture is made as though the opponent's Pawn had moved only one square forward. This complex rule was created to prevent a Pawn from using the two-square first-move rule to pass an opponent's Pawn and avoid capture.
En prise: French for "in a position to be taken". A Chessman is 'en prise' if it is left or moved to a square where it can be captured without loss to the capturing player. A piece 'en prise' is often the result of a blunder. Commonly used by English-speaking players that means "in prison."
Epaulet Mate: Checkmate where the losing King is on the edge of the board with one of his own Chessmen on both sides of the King on the edge.
EPD: Extended Position Description is a standard for describing Chess positions along with an extended set of structured attribute values using the ASCII (American Standard Code for Information Interchange) character set. It is intended for data and command interchange among Chess playing programs. It is also intended for the representation of portable opening library repositories. The first four fields of the EPD specification are the same as the first four fields of the closely related FEN specification. Like FEN, EPD can also be used for general position description. However, unlike FEN, EPD is designed to be expandable by the addition of new operations that provide new functionality as needs arise. A text file composed exclusively of EPD data records should have a file name with ".epd" as the suffix.
Here is what the board position after 1.e4 looks like in EPD format:
"rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1"
Equal: A common intermediate result in a game of Chess that either side may win, lose, or draw.
Equalize: To achieve a position where the opponent's initiative is negated. For example, white usually has the initiative in the opening and black works to equalize, or overcome this initiative. At this point, both sides have an equal chance of winning.
Equal position: Any Chess game position from which a player can win, lose, or draw. Equal positions offer equal chances for both sides with alert play.
Escape square: A square to which a King in check can move, also called flight square.
Euler: A closed Knight’s tour.
Evergreen Game: Famous Chess game played in 1852 by Anderssen and Dufresne (Level-1). It was thus named because Steinitz felt it would always remain as fresh as the day it was played.
Exchange: The trading of a piece for an enemy piece, usually pieces of equal value. However, the presence of amplifying verbage signifies an unequal trade; most often the advantage of a Rook for a Bishop or Knight. If you have a Rook and your opponent has a less valuable Bishop, you are said to have "won the exchange". You are "up an exchange" or an "exchange ahead." Likewise, "sacrificing the exchange" is giving up a Rook for a less valuable Knight or Bishop.
Exchange advantage: The trading of a piece for an enemy piece of greater value.

 
Fairy Chess: Non-orthodox Chess problem compositions. A problem or puzzle where some official rules of the traditional game of Chess are suspended or changed.
Family check: Bogoljubow's lighthearted term for a Knight fork which includes an attack on the King.
FEN: Forsythe-Edwards-Notation. FEN is the standard for describing Chess positions using the ASCII (American Standard Code for Information Interchange) character set. It is intended as a standard position notation for Chess programmers, for page layout programs, and for confirming position status for e-mail competition. Six FEN fields specify the piece placement, the active color, the castling availability, the en passant target square, the halfmove clock, and the fullmove number. The first four fields of the FEN specification are the same as the first four fields of the closely related EPD specification. Like FEN, EPD can also be used for general position description. However, unlike EPD, FEN is not as expandable. FEN provides no means to add new operations that provide new functionality as needs arise. A text file composed exclusively of FEN data records should have a file name with ".fen" as the suffix.
Fers: The medieval name for the piece we now call the Queen, derived from the Persian word "Vizier".
Fianchetto: An Italian term that means "on the flank" and applies only to Bishops. A Fianchetto involves placing a white Bishop on g2 or b2 or a black Bishop on g7 or b7. This manoeuvre places the Bishop to a position from which it controls the longest diagonal. A word derived from the Italian word 'fianco' meaning flank.
FIDE: The acronym for Fedération Internationale des Échecs, the international Chess Federation which organizes the titles, awards and the international rating system.
FIDE Master: Title awarded by FIDE and is ranked below International Master.
Figurine notation: A system of recording the moves of a Chess game similar to Algebraic Notation except that small pictures of the pieces and Pawns are substituted for their names. This method has been popularized by published articles in newspapers and other periodicals.
File: A vertical column of eight squares. This column of squares runs from the top of the board to the bottom. Designated in algebraic notation as the a-file, b-file, c-file, d-file, e-file, f-file, g-file and h-file. The players' Kings start the game on the same file.
Fingerfehler: German for finger-slip, a description of an obvious but bad move made without thinking.
First Board: Also called top board, a term to describe the board in a team match which usually has each team's strongest player.
Fischer clock: A clock which, in addition to serving the usual functions of a Chess clock, adds a certain amount of time to each player's clock after each move, in order to avoid desperate time scrambles at the end of a game, which often result in poor moves.
Fish: Derogatory term for a Chess player of little skill, poor experience or a bad player.
Fixed Pawn: A Pawn whose advance is blocked by an enemy piece.
Flag: Part of an analog Chess clock. As the minute hand on the clock nears the 12, the flat is pushed upward. When the minute hand reaches 12 it no longer holds up the flag and it falls. The falling of the flag indicates that the player's time has expired, and if the requisite number of moves have not been played, the player is said to "lose the game on time" (i.e. the game is lost because time ran out, not because of the position on the board, although many games are lost on time when the position is poor and the losing player uses large amounts of time in an effort to try to find a way to save the game).
Flank: The a, b, and c files on the Queenside and the f, g, and h files on the Kingside.
Flight square: A square to which a King in check can move, also called escape square.
FM: FIDE Master.
Fool's mate: The shortest possible Chess game ending in checkmate:
1. g4 e5 (or e6) 2. f4 (or f3) Qh4 mate. It is so named because white must play foolishly to allow this mate.
Forced: A move or set of moves that are required (forced) to avoid a lesser game result.
Forced mate: A sequence of moves that lead to a checkmate no matter what the opponent responds.
Forced move: A move for which there is only one reply (or if more than one reply, all but one are undesirable).
Fork: An attack on two or more pieces simultaneously. Though any Chess piece (except a Rook- Pawn) can execute a fork, the Knight makes a specialty of it.
Forsythe Notation: Compact and simple means of recording a Chess position also known as "FEN" (Forsythe-Edwards-Notation), devised by Scottish player David Forsythe. Beginning at the top, left-hand corner of the board (a8) the position of the Chessmen as well as the unoccupied squares are recorded, rank by rank. White's men are recorded with capital letters, and Black's with lowercase letters.
For example, the starting position is notated:
"rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR"
Fortress: A Chess position that cannot be effectively attacked or broken down even with superior material advantage.
Frontier line: Nimzowitsch's term for an imaginary line running between the fourth and fifth ranks.

 
Gambit: An opening maneuver in which at least a pawn is offered in return for a strong position, a chance to attack or gaining tempo which permits development. A gambit usually involves the sacrifice of a Pawn or minor piece when a game is in a complex phase such as the opening or middlegame. A gambit is difficult, but possible to refute. An apparent sacrifice of material for a clear advantage is called a combination; not a gambit.
Game of the century: Widely-used, descriptive term for the Fischer-Byrne game (a Grünfeld Defense) in the 1956 Rosenwald tournament. Fischer, 13 year's old at the time, mated IM Byrne using a Queen and Rook sacrifice. Kmoch used the term "Game of the Century" in his Chess Life article to refer narrowly to Chess played by youngsters.
Gelbfuhs Score: Tie-breaking system applicable to tournaments where players do not all play the same number of rounds. An individual's Gelbfuhs Score equals the sum of scores of the players beaten, divided by the number of games played; plus one-half the sum of scores of players with whom draws were scored, divided by the number of games played. The Gebfuhs Score is equal to the Sonneborn-Berger score when all players play the same number of games.
Gens una sumus: Latin for "We are one family or We are one race". The official motto of FIDE.
GM: Abbreviation for International Grandmaster.
GMA: The ill-fated Grandmasters Association (GMA) under Kok’s chairmanship showed how Chess should be organised with a professional circuit that hosted the memorable World Cup series under the tournament directorship of Lubos Kavalek.
Good Bishop: A Bishop free to operate without interference from its own Pawns and thus is very mobile. Such Bishop is very active because it is positioned on a square of the opposite colour to the squares on which most of its Pawns are stationed.
Göttingen Manuscript: A Latin document of 33 pages containing analysis of openings and Chess problems. Housed in the University of Göttingen Library, it is believed to have been written by Lucena, circa 1500.
Grading: A numerical representation of the strength of a Chess player based upon his results in games against other graded players. In the US, the term rating is used in place of grading.
Grandmaster: A title awarded by FIDE to players who meet an established set of performance standards, including a high Elo rating. It is the highest title (other than World Champion) attainable in Chess. Once earned, a Grandmaster title cannot be taken away.
Great Bare King: Type of win where the victor checkmates the opponent on the same move that also leaves the loser with a bare King.
Guéridon: French for pedestal table. A position where a checkmated King has two defenders on diagonally adjacent squares and is attacked by the enemy queen which sits on an immediately adjacent square.

 
Half-open file: A file that contains none of one player's Pawns but one or more of his opponent's.
Half-pin: A pin in which the Chessman subject to the pin may move along the same line (file, rank or diagonal) which it shares with the attacker.
Handicap: A means of trying to equalize chances in a game played between opponents of greatly different strengths. There are numerous methods of implementing a handicap; the stronger player might (among other things): treat a draw as a loss; play several opponents at the same time; give his opponent more time on the clock; give his opponent two moves in a row at the opening of the game; or remove one or more of his men from the board before play begins.
Hang, Hanging To be unprotected and exposed to capture. Slang term to describe a piece left en prise.
Hanging Pawns: Steinitz's term for two adjacent Pawns which are on the fourth rank, cannot be supported by other Pawns, are not passed Pawns, and which are on half-open files.
Harkness Score: Tie-breaking system applicable to Swiss tournaments. The scores of the opponents of each of the tied players are summed, first leaving out the highest and lowest scores. In tournaments with a large number of rounds, two or more of the highest and lowest scores may be deleted. Also called the Median Score.
Hastings: A town in Sussex, England, on the south coast. Since 1920, a Chess congress is held there which begins in late December.
Heavy Piece: A Queen or Rook. Sometimes called a major piece.
Helpmate: A special Chess problem invented by Max Lange where both sides cooperate in mating the black King. Black moves first. Helpmate problems are a form of fairy Chess.
Hole: A square that cannot be defended by a Pawn. Such a square makes an excellent home for a piece because the piece cannot be chased away by hostile Pawns. Also known as outpost.
Home Pawns: A Kmoch's term for the Pawns in front of the castled King.
Home side: Kmoch's term for the flank which contains the castled King.
Horse: An informal word for a Knight. This term is used most often by children.
Howler: A bad move. A mistake that overlooks a simple tactical response. (See also Blunder)
Hypermodern: A school of thought that arose in reaction to the classical theories of Chess. The Hypermoderns insisted that putting a Pawn in the center in the opening made it a target. The heroes of this movement were Richard Réti and Aaron Nimzovich, both of whom expounded the idea of controlling the center from the flanks.

 
ICCA: International Computer Chess Association. The association which organizes the World Computer Chess Championship held every three years, and the World Microcomputer Chess Championship held every year.
ICS: Internet Chess server.
IGM: International Grand Master.
Illegal move: A move which is in violation of the Laws of Chess. If an illegal move is discovered during the course of a game, the game will be returned to the point it was before the illegal move was made. The player who made the illegal move must move the piece he had previously moved illegally, if he can make a legal move with that piece. Otherwise, he is permitted to make any legal move.
Illegal position: A position which is not the result of a series of legal moves. Thus, an illegal move necessarily leads to an illegal position. Other sources of illegal positions include: incorrect positioning of the Chess board and incorrect arrangement of the Chessmen either at the beginning of the game or at the time an adjourned game is resumed. If it is possible, the position must be corrected, otherwise a new game must be played.
IM: Abbreviation for International Master.
Immortal Game: Famous Chess game played between Adolf Anderssen and Lionel Kieseritzky. This game established a glittering reputation for Anderssen and an example of the KIs-BS Gambit which was played at Simpson’s-in-the-Strand (one of London’s finest Chess salons).
Indian Defenses: A family of openings in which Black replies 1...Nf6 to White's 1. d4. There does not seem to be much agreement on the origin of the term, but most historians believe it derives from the style of play in India where, because Pawns did not have the right to make a two-square initial move, games tended to be leisurely and conservative.
Initiative: Term to describe the advantage held by the player who has the ability to control the action and flow of the game thus forcing the opponent to play defensively. A player able to make threats to which his opponent must react, he is said to "possess the initiative." This is usually due to better placement of the chessmen and easier access to weaknesses in the opponent's position.
Inner Pawn: Kmoch's term for a Pawn on any file except the a- or h-file.
Inside Chess: Chess magazine founded in 1988, with Yasser Seirawan as editor. It is published in Seattle, Washington (USA).
International Arbiter: A title first awarded by FIDE in 1951. A candidate is nominated by his federation, and may be selected by the qualification committee if he: has a complete knowledge of the rules of Chess and FIDE regulations; is objective; has knowledge of at least two FIDE languages (English, French, German, Spanish, and Russian); has experience in controlling four important tournaments, two of which must be international.
International Chess Magazine: A Magazine founded and edited by Wilhelm Steinitz and published in New York from 1885 to 1891. Steinitz wrote most of the material himself.
International Grandmaster: Title established in 1950 and awarded by FIDE. FIDE has detailed requirements for the title, which is awarded to only the best players in the world. A player with a FIDE Grandmaster title, often abbreviated GM, usually has an Elo rating of at least 2500.
International Master: Title established and awarded by FIDE, often abbreviated IM. An IM is a stronger player than a FIDE Master, but not as strong as an International Grandmaster, and usually has an Elo rating of at least 2400.
International Rating list: A list of the world's strongest players, compiled by FIDE using the Elo rating scale. It was first published in July 1971.
International Woman Grandmaster: Title established in 1976 and awarded by FIDE to the world's strongest women players.
Internet Chess Server: Any of several computers on the Internet (an international computer network) which permit computer users to play real-time Chess games with other players on the Internet. People connected to the ICS can also observe other games in progress and communicate with each other.
Interpose: To place a piece or a Pawn between an enemy attacking piece and the attacked piece.
Interposition: The movement of a piece in between a piece which is attacked and its attacker.
Interspan: Kmoch's expression to denote the number of squares on a file that separate Pawns of opposite color. The greatest interspan occurs at the beginning of the game.
Interzonal Tournament: One tournament in a series of competitions held by FIDE to select a challenger to the World Champion. Winners of the 14 Zonal championships compete in the Interzonal tournaments, which were first held in 1948. The top players from the Interzonals play in the Candidate matches which conclude when a challenger emerges.
Isolated Pawn: A Pawn whose adjacent files contain no Pawns of the same color. An isolated Pawns is weak because it, and the square in front of it, cannot be defended by other Pawns. An isolated Pawn is consider a fundamental weakness in a Chess position because it can be attacked. Its defense requires pieces that are better employed in other plans.
IWM: International Woman Master.

 
J'adoube: A French word commonly used by English-speaking players that means 'I adjust'. A notice to one's opponent that one is about to adjust the position of a piece on its square with no intention to move the piece to another square.

 
K: Abbreviation for King.
Karnamak: Persian epic written about 600 AD. Possibly the first piece of literature to refer to Chess.
Key: The unique, first move in the solution to a Chess problem.
KIA: King's Indian Attack.
Kibitz: To comment during a game, or during analysis following a game, within the hearing of the players. The term is often used in a pejorative sense, and is in many occasions applied to the comments of a spectator for whom the players have little respect.
Kibitzer: One who kibitzes.
Kibitzing: kibitzing - Observing and commenting on a Chess game, usually in a manner that disturbs the players.
KID: King's Indian Defense.
King: The most important of the Chessman, and consequently usually the largest. The King may move one square in any direction, and a game is over when the King is checkmated.
King Hunt: A prolonged attack on the opponent's King which usually dislodges it from a shielded, defensive position with a series of checks and sacrifices. A successful King-hunt ends in checkmate.
Kingside: The half of the board made up of the e, f, g, and h files. Kingside pieces are the King, the Bishop next to it, the Knight next to the Bishop, and the Rook next to the Knight.
King's Pawn opening: The move 1. e4. Bobby Fischer's favorite opening. Moving the King Pawn opens lines for the King Bishop and the Queen, occupies a key central square and prevents the opponent from occupying squares diagonally in front of the Pawn.
Knight: A Chess piece which moves either two squares vertically and one square horizontally or two squares horizontally and one square vertically. In the first step of this move, the Knight may pass "through" squares already occupied. The Knight's move has not changed since Chess was devised.
Knight Fork: Any double attack by a Knight.
Knight's Tour: A Chess puzzle whereby the Knight is moved 64 times, landing on each square only once. A solution is called "re-entrant" if the Knight finishes on a square which is a Knight's move away from the square where it began.
Kt: Old abbreviation for Knight.

 
Ladder: A fluid method of ranking Chess players within a club or other group. The ladder is usually established by listing players according to their Chess rating. Any player may challenge someone one step above them on the ladder (sometimes two or more places). If the challenger wins, he moves up the ladder and his opponent moves down.
Lasker Trap: A trap in the Albin Counter-Gambit, resulting in a winning position for Black: 1. d4 d5 2. c4 e5 3. dxe5 d4 4. e3 Bb4+ 5. Bd2 dxe3 6. Bxb4 exf2+ 7. Ke2 fxg1=N+.
Laws of Chess: The rules which govern the play of the game. During the 1850s, Staunton was one of many players who first sought to establish a unified set of Chess laws. FIDE established its own laws of Chess in 1929.
Le Palamede: The first Chess magazine, published in Paris from 1836 to 1840. La Bourdonnais was the editor and claimed he had 236 subscribers.
L'Échiquier: Belgian magazine published from 1925 to 1939. It was the first to use Figurine Notation.
Lee: Kmoch's expression for the part of a rank divided by a Pawn having the fewer number of squares.
Legal move: Move permitted by the Laws of Chess.
Légal's Mate: A mating sequence appearing in the game between M. de Kermar Légal and Saint Brie in about 1750: 1. e4 e5 2. Bc4 d6 3. Nf3 Bg4 4. Nc3 g6 5. Nxe5 Bxd1 6. Bxf7+ Ke7 7. Nd5 mate.
Leucopenia: Kmoch's expression for a lack of control of the light squares.
Lever: Kmoch's term for a white and a black Pawn which are diagonally adjacent so that either can capture the other.
Lewis Chessmen: Chess pieces made of walrus tusk discovered on the Isle of Lewis (outer Hebrides) in 1831. They were probably made in the 11th or 12th century and now are on display in the British Museum.
Light Bishop: A Bishop which moves on light-colored squares.
Light Piece: Another expression for minor piece: a Bishop or a Knight.
Lightning Chess: Another term for speed or Blitz Chess.
Linares: Small city in south-central Spain which has been the site of numerous strong, International tournaments.
Little Bare King: A win which includes baring the King, but in which the capture which bares the King does not also deliver checkmate.
Living Chess: The performance of a Chess game where the Pawns and pieces are represented by real people. The performance may be a re-enactment of a famous game or a new game.
Long Algebraic Notation: A form of algebraic notation. A move is designated by a letter indicating the piece moved, plus the square the piece moves from as well as the square the piece moves to (e.g. Bc1-g5). Pawn moves are designated by the starting square an the destination square (e.g. e2-e4).
Long Castling: Expression sometimes used to describe castling Queen-side.
Longest Game: The longest game played by top players was played in Belgrade in 1989. I. Nikolic and Arsovic drew in 269 moves.
Loose Lever: Kmoch's term for a lever such that either side have the option of capturing or moving past the opponent's Pawn.
Lose: A common result in a game of Chess when the losing side is checkmated or resigns before checkmate. A lose may result when a player makes the last mistake or blunder.
Losing chances: The probability in any complex and roughly equal position that one side may successfully lose a game of Chess by thoughtless play. Usually, winning, losing, and drawing chances are judged as either good or poor. If a position is sufficiently unclear that either side may win, lose, or draw, then that position is estimated to give both sides equal chances.
Losing on Time: A player loses on time if he has not completed the required number of moves in the allotted time. If the opponent does not have sufficient material to prove a win, the game is drawn.
Losing the Exchange: To exchange a rook for either a Bishop or Knight.
Lost position: Any Chess game position from which a player must lose with accurate play. Many complex lost positions may still offer winning or drawing chances with alert play. It is unknown whether the starting position is also a lost position.
Lucena Position: A well-known and well-analyzed Rook and Pawn ending first analyzed in a book by Lucena, published in 1497.
Luff: Kmoch's expression for the part of a rank divided by a Pawn having the greater number of squares.
Luft: A German term that means 'air'. In Chess, it means to give the King breathing room. It describes a Pawn move made in front of the King of the same color to avoid back rank Mate possibilities.

 
Major Pieces: The Queen and Rooks. Because of the number of squares they command (a Queen can command 27 squares, not counting the one she occupies, a rook 14) they are considered the heavy artillery of Chess.
Majority: A player's numerical superiority of Pawns on one flank. Such a majority is important because it may lead to the creation of a passed Pawn.
Marienbad 1925 Tournament won by Rubinstein and Nimzowitsch, followed by Marshall, Torre, Reti, and Tartakower.
Master: In the U.S., a player with rating of 2200 or more. If a player's rating drops below 2200, the title is rescinded. There are about 90 Grandmasters in the entire world. It is also the highest ranking in Chess earned by competing in major tournaments.
Mate: Short for Checkmate. When a King cannot avoid capture.
Mate in two: A common Chess problem where white on the move must checkmate black in two moves despite black's best reply. Mate in three, four, or more moves are also common training exercises.
Material: The total value in points of a player's pieces on the Chessboard. A material advantage is when a player has more pieces on the board than his opponent or has pieces of greater value. Material advantage is one key quality in assessing a Chess position.
Match: A contest between two players only, as distinguished from a tournament. The term often refers to a contest of many games, but is sometimes used to describe a single game. The first major Chess match was between La Bourdonnais and McDonnel in 1834. Also, a contest between two teams, played on several boards.
Mating Attack: An attack which aims at Checkmate.
Mating net: A position or series of moves that leads inexorably to one in which the King must be mated or, a position where one player has mating threats. This can be accomplished with the pieces working together to trap and checkmate the enemy King.
Mating Sacrifice: A material sacrifice made to achieve Checkmate.
MCO: Abbreviation for Modern Chess Openings.
Mechanical Move: A move made with little thought because it seems to be obvious.
Median Score: A tie-breaking system applicable to Swiss tournaments. The scores of the opponents of each of the tied players are summed, first leaving out the highest and lowest scores. In tournaments with a large number of rounds, two or more of the highest and lowest scores may be deleted. Also called the Harkness Score.
Mephisto: Constructed by Charles Godfrey Gumpel and first demonstrated in London in 1878, Mephisto was described as a Chess playing automaton. It was in fact a device which contained a person who played Chess. Operated by Isidor Gunsberg, it was the first automaton to win a Chess tournament.
Middlegame: The second phase of the game following the opening, and the one in which much of the action takes place. The development of the pieces is complete or nearly complete and many pieces are captured or traded as the players pursue their creative plans. With many pieces on the board and possibilities of attack on all sides, the King normally stays well hidden in this phase.
Miniature: Also called brevity, a short game—usually about 20 moves or less. Many writers use the term only for entertaining games and therefore do not generally include draws in this category. Any Chess problem featuring seven or fewer pieces.
Minor Exchange: Tarrasch's term for the exchange of a Knight for a Bishop. Because he preferred Bishops, he described the player who gave up the Knight as winning the minor exchange.
Minor pieces: The Bishops and Knights. A Knight can command eight squares, a Bishop thirteen.
Minority Attack: The advance of one or more Pawns on a flank where the opponent has a Pawn majority. The objective of a minority attack is to create a isolated Pawn weakness in the enemy position.
Mobility: The ability to move about freely on the board.
Morals of Chess, The: A 1779 essay by Benjamin Franklin outlining the merits of Chess and advocating a specific set of rules of etiquette for play.
Muse of Chess: Another term for Caissa.
My System: Aaron Nimzowitsch's immensely influential work describing his theory of Chess, first published in English in 1929.
Mysterious Rook Move: The movement of a Rook to a closed file to discourage the opponent from making a freeing move because such a move would bring the Rook into play, a strategy advocated by Nimzowitsch.

 
N: Abbreviation for Knight.
National Chess Day: October 9th, 1976. US President Gerald Ford set the day aside "to give special recognition to a game that generates challenge, intellectual stimulation, and enjoyment for citizens of all ages."
National Master: Title granted by national federations to strong players, usually those with a sustained ELO rating of 2200 or above.
Neo-Romantic: A style of play developed in the twentieth century. This style incorporates the romantic tradition of aggressive attack, and couples this aspect of play with a strong defense.
Neustadtl Score: Another name for the Sonneborn-Berger Score.
New in Chess: Monthly Chess magazine edited by Jan Timman and quarterly volumes edited by Gennadi Sosonko published in Holland since 1984.
Nimzo-Indian Defense: One of the Indian defenses, characterized by the sequence: 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4. Named after Aaron Nimzovitch.
NM: Abbreviation for National Master.
Norm: The number of points a player in an international tournament must score to gain one qualification for a FIDE title. The weaker the tournament, the more points a player must score for any given norm.
Normal Opening: An old name for the French Defense.
Normal Position: The position in the Evans Gambit after: 1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 Bxb4 5. c3 Ba5 6. d4 exd4 7 .0-0 d6 8. cxd4 Bb6.
Notation: System for recording moves and positions of a Chess game - Algebraic Notation, Long Algebraic Notation, Descriptive Notation, Figurine Notation, Forsythe Notation, Udemann Code, etc.
Novice: A beginning Chess player.

 
Obstructive Sacrifice: A material sacrifice to hinder an opponent's development.
Occupation: A Rook or Queen that controls a file or rank is said to occupy that file or rank. A piece is said to occupy the square it is sitting on.
Official Rules of Chess: Official FIDE publication setting forth the Laws of Chess.
Open: Short for Open game or Open file. A term used to describe a position where Pawns do not block the mobility of the pieces around some or all of the board. The opposite of a closed position. Also refers to a type of tournament in which any strength of player can participate.
Open file: A file cleared of Pawns. It offers a corridor for attack, especially if occupied by doubled Rooks. A file is still open even if it is occupied by pieces other than Pawns.
Open game: A position characterized by many open ranks, files, or diagonals, and few center Pawns.
Open Tournament: A tournament which is open to any player.
Opening: The start of a Chess game. The first phase of the game before the middlegame and endgame, in which players try to rapidly develop their pieces, gain room for their pieces to maneuver, and on bringing their Kings to safety. Many promising opening lines of play are analyzed and documented extensively in texts and computer databases. The basic goals of the opening are to develop pieces as quickly as possible.
Openings: The more-or-less standardized and analyzed patterns of moves that both sides make at the start of a game. Some are named after people (Ruy Lopez), some after places (Budapest Counter-Gambit), some after pieces or moves (Four Knights Defense). Some are descriptive (Giuoco Piano, or quiet game).
OTB: Abbreviation for Over-The-Board.
Opposite colored Bishops: Bishops can only move on one color square determined by their original position. Thus we have light- and dark-colored squared Bishops. If only two opposing Bishops on opposite colored squares are captured from the board, then opposite colored Bishops remain. (See also Bishop pair.) The opposite colored Bishops characterize Chess play as asymetrical. The opposite colored Bishops cannot challenge or capture each other. Therefore, the attacking side often has the advantage in a middlegame with opposite colored Bishops. However, opposite colored Bishop endgames are often drawn, because neither site can control both colored squares to force the advance of a Pawn.
Opposition: A position in which opposing Kings stand on the same rank, file or diagonal, usually in an endgame, separated from each other by only one square. The player whose move brings the Kings into opposition holds an advantage that, in an endgame, can be decisive.
Outpost: A square that supports a piece. Term coined by Nimzowitsch; a piece placed on a square (on an open or half-open file) on the opponent's side of the board, protected by a Pawn, which cannot be attacked by an enemy Pawn. The power of the piece on the outpost can be so strong the opponent may be forced to exchange it, even at the cost of material or positional loss.
Outside Passed Pawn: A passed Pawn away from most of the other Pawns on the board.
Over the Board: A description of games played face to face, as opposed to correspondence Chess or email Chess.
Overload: A situation where a Pawn or piece must perform too many defensive functions, so that if one it is forced to perform one function a weakness will be created.
Over-protection: Nimzowitsch's concept of concentrating many pieces
and/or Pawns--even more than might seem necessary--on an important square. This creates a strong square which interacts beneficially with the over-protecting pieces.
Overextension: When space is gained too fast. By rushing his Pawns forward and trying to control a lot of territory, a player can leave weaknesses in his camp or can weaken the advanced Pawns themselves. He is then said to have overextended his position.
Overworked piece: A piece that is required to single handedly defend too many other pieces.

 
P: Abbreviation for Pawn.
Pairings: A listing of who plays whom at a tournament.
Palamède, Le The first Chess magazine. It was founded in 1836 by La Bourdonnais and named after the ancient Greek inventor Palamedes. Publication ceased in 1847.
Parry a Check: To place a Chessman between the King in check and the checking piece. This is one of three ways to meet a check, the other two being moving the King or capturing the checking piece. If a player in check cannot employ one of these three ways to meet the check, the King is checkmated and the game is over.
Parsing: Analysis, intended for use by NL (natural language) parsing researchers and others interested in the automated extraction of Chess data from text articles. A more complete usage requires actual game parsing. After reading the game, a parse_game() method is called, and as a result we have the moves available in an array, comments and errors in two hashes, where the keys are the move numbers and the values are comments or errors.
Passed Pawn: A Pawn unopposed, on its own or adjacent files, by a Pawn of another color. By being advanced to the eighth rank it can become any piece its owner chooses. A passed Pawn, therefore, is a source of worry for the other side and a precious advantage for its owner. Two united passed Pawns on adjacent files constitute a formidable weapon.
Passive: Description of a move which contains no threats. Also, refers to a piece with limited mobility, i.e. a piece which is not active.
Patzer: A weak player. Sometimes used more specifically to describe a weak player who either does not recognize his deficiencies or who may boast of his ability.
Pawn: Physically, the smallest unit on the Chessboard. A Pawn moves straight ahead but captures diagonally. Originally, a Pawn could only ever move a single square forward. During the renaissance a player was given the option of moving a Pawn forward two squares on its first move. If a Pawn reaches the eighth rank, it must be promoted to another piece.
Pawn break: The possibility of opening up a blocked Pawn structure by advancing a Pawn.
Pawn centre: A pair or group of Pawns of the same colour that occupy the central squares of the board.
Pawn chain: A string of two or more Pawns of the same colour along a diagonal.
Pawn grabbing: Deprecating term to describe the act of winning Pawns at the expense of development or countering an opponent’s attack. Also known as Pawn snatching.
Pawn island: A Pawn or group of Pawns separated from other Pawns of the same colour.
Pawn push: Another term for Pawn Storm.
Pawn roller: Another term for Pawn Storm.
Pawn storm: The general advance of two or more connected Pawns. A Pawn storm may be employed to attack the King, to promote one of the Pawns, to keep some of the opponents’ pieces away from another part of the board, among other things.
Pawn structure: All aspects of the Pawn setup. Also referred to as the Pawn skeleton or the arrangement of a player's Pawns on the board.
PCA: Abbreviation for Professional Chess Association. After a long term friction with the International Chess Organization (FIDE), Garry Kasparov and Nigel Short created in 1993 a rival Organization: The Professional Chess Association (PCA).
Perpetual Check: A sort of infinite cycle in which one side gives check, the other side gets out of check, the first side checks again in the same way - being unable to do otherwise without risking the loss of the game - and so on. It constitutes a draw.
Perpetual pursuit: Similar to a Perpetual Check, except that the pursued piece is a Bishop, Knight, Rook, or Queen, instead of the King.
Petite combination: A combination that involves only a few moves.
PGN: Portable Game Notation, a standard text system of chess notation used on Chess viewers programs and designed for the representation of chess game data using ASCII text files. PGN is structured for easy reading and writing by human users and for easy parsing and generation by computer programs. A text file composed exclusively of PGN data records should have a file name with ".pgn" as the suffix.
Phalanx: Pawn structure where two or more Pawns of the same color are side-by-side, i.e. on the same rank and on adjacent files.
Piece: Any Chess piece other than the Pawn, but usually referring to a Bishop or Knight.
Pig: Slang for Rook. Rooks doubled on the 7th rank are commonly referred to as pigs on the 7th.
Pin: A position in which a piece may not be moved because another piece would be subject to capture. If the piece subject to capture is the King, the Pin is absolute and the pinned piece cannot legally be moved. When the piece is not the King, the tactic is called a 'relative Pin'.
Plan: A short or long range goal on which a player bases his moves. A method or line of play designed to improve a position. A Chess player should always have a plan.
Ply: One play in a Chess game -white or black, which is one half of one complete move pair. Computers have the capability to consider the probable result of an almost infinite number of move/countermove strategems against each move made by a player (except for book openings). These levels of move combinations are referred to as "plies" or half-moves in computer terminology.
Point count: A system that gives the pieces the following numeric values: King= priceless; Queen= 9 points; Rook= 5 points; Bishop= 3 points; Knight= 3 points; and Pawn= 1 point.
Poisoned Pawn: A Pawn (often White's Pawn on b2) which is undefended during the opening but which if taken, often permits the player who gave up the Pawn to engage in a strong attack or to later win the piece taking the Pawn.
Position: The arrangement of Chess pieces. The player whose pieces have better placement is said to have a "positional advantage."
Positional Chess: A move or style of play based on long range considerations. The slow buildup of small advantages is said to be positional.
Positional Sacrifice: A sacrifice of material which improves the position of the sacrificing player.
Preventive Sacrifice: A Sacrifice made to prevent the opponent from castling.
Promotion: Also called 'Queening'. When a Pawn reaches the 8th rank, it can be promoted to a Bishop, Knight, Rook, or Queen of the same color. A pawn who survives to reach the eighth rank is rewarded by promotion to a piece of higher value.
Protected passed Pawn: A passed Pawn that is under the protection of another Pawn.

 
Q: Abbreviation for Queen.
Queen: The strongest piece on the board (but second in size to the King) and which combines the moves of the Bishop and the Rook, namely is able to move along diagonals, ranks, or files as far as such lines are unobstructed.
Queening a Pawn: A special case of Pawn promotion to a Queen. This phrase is often used to describe promotion in general, because a Pawn is usually promoted to a Queen; the highest valued option.
Queening Square: The 8th rank square to which a Pawn is moved, and then must be promoted. This promotion square is called the Queening