The Essential Chess Glossary – Terms, Jargon, and Definitions

A quick reference for all the terms, jargon, and concepts you'll encounter in the world of chess. Click a letter or scroll down to find a term.

A

Adjudication: The process of a chess arbiter determining the result of an unfinished game based on the position and a player's analysis.
Adjournment: The temporary suspension of a game to be continued later. Rare in modern play due to computer analysis.
Alekhine's Gun: A powerful formation where a Queen lines up behind two Rooks on a single file to create triple pressure.
Algebraic Notation: The standard method for recording chess moves (e.g., e4, Nf3) used in all modern competitions.
Annotation: Commentary, notes, and analysis added to a recording of a game, often using symbols like '!' and '?'.
Arbiter: The referee of a chess tournament responsible for enforcing rules, settling disputes, and ensuring fair play.
Armageddon: A tie-break game where White has more time (e.g., 5 mins) but must win; Black has less time (e.g., 4 mins) but wins if the game is drawn.
Artificial Castling: Manually moving the King and Rook over several turns to achieve a castled position when normal castling is illegal.
Attack: An aggressive action attempting to capture a piece, checkmate the King, or create weaknesses in the opponent's camp.

B

Back Rank: The first rank (for White) or eighth rank (for Black) where the major pieces start.
Back-Rank Mate: A checkmate delivered by a Rook or Queen on the 8th rank because the King is trapped by its own pawns.
Backward Pawn: A pawn that has fallen behind its neighbors and cannot be supported by other pawns. It is a static structural weakness.
Bad Bishop: A bishop restricted by its own pawns (on the same color squares), reducing its mobility.
Battery: Two or more pieces (like Queen+Bishop or Rook+Rook) lined up on a file or diagonal to multiply their power against a target.
Bishop: A minor piece that moves diagonally. Each player starts with two: a light-squared bishop and a dark-squared bishop.
Bishop Pair: Possessing both bishops in an open position is often a statistical advantage over a Knight and Bishop or two Knights.
Black: The designation for the player who moves second in the game. The black pieces are dark-colored.
Blindfold Chess: Playing chess without looking at the board, relying entirely on memory and visualization skills.
Blind Swine: Two Rooks on the opponent's 7th rank, devouring pawns and locking the enemy King. A devastating endgame pattern.
Blitz: Fast chess! Typically 3 to 5 minutes per player. It requires intuition and rapid pattern recognition.
Blockade: Placing a piece (ideally a Knight) directly in front of an enemy passed pawn to physically stop it from advancing.
Blunder: A severe mistake that loses material or the game immediately. Annotated as '??'.
Brilliancy: A game containing a beautiful, original, and correct strategic concept or sacrifice.

C

Candidate Master (CM): A FIDE title ranking below FIDE Master, usually requiring a 2200 rating.
Candidate Move: A shortlist of moves you consciously evaluate before making a decision. The first step of structured calculation.
Castling: The only move where two pieces move at once (King and Rook) to get the King to safety and activate the Rook.
Center: The critical squares e4, d4, e5, and d5. Controlling the center is the primary goal of the opening.
Centralization: Bringing pieces towards the center where they control the most squares and can easily move to either flank.
Checkmate: The end of the game. The King is under attack (check) and has no legal way to escape.
Clearance: Sacrificing or moving a piece to "clear" a square for a more powerful piece or line of attack.
Closed Game: A position with locked pawn chains, leading to slow maneuvering rather than open tactical lines.
Combination: A forced sequence of moves, often involving a sacrifice, that leads to a tangible advantage.
Compensation: Strategic advantages (like time, space, or attack) gained in return for sacrificing material (like a pawn).
Connected Pawns: Pawns on adjacent files that can protect each other. A significant strength in endgames.
Correspondence Chess: Games played over days or weeks per move, historically via mail but now via server. Allows for deep research.

D

Dark Square Complex: A situation where a player is weak on dark squares (due to pawn moves or missing a bishop), allowing the opponent to dominate them.
Decoy: A tactic that lures an enemy piece to a "poisoned" square where it can be attacked or creates a weakness.
Deflection: Forcing a piece to move away from a square it was defending, leaving a target vulnerable.
Desperado: A piece destined to be lost that sacrifices itself for the maximum possible damage before it leaves the board.
Development: Moving pieces from the back rank to active squares. "Develop your pieces!" is the golden rule of the opening.
Discovered Attack: Unleashing an attack by moving a piece that was blocking the line of fire of a long-range piece (Bishop, Rook, Queen).
Discovered Check: A powerful variant of the discovered attack where the revealed piece delivers a check to the opponent's King.
Double Attack: A move that creates two threats at once. See Fork.
Doubled Pawns: Two pawns of the same color on the same vertical file. Usually a structural weakness, but can control key squares.
Draw: A tied game. Can happen via Agreement, Stalemate, Repetition, 50-Move Rule, or Insufficient Material.

E

Elo Rating: The mathematical system used to calculate the relative skill level of chess players. Named after Arpad Elo.
Endgame: The final phase of the game where few pieces remain. King activity and Pawn promotion become the main goals.
En Passant: A special pawn capture rule: "In passing." If a pawn moves two squares and passes an enemy pawn, it can be captured as if it moved only one square.
En Prise: French for "in a position to be taken." A piece left hanging or unprotected.
Exchange: Trading pieces. "Winning the Exchange" specifically refers to winning a Rook for a Minor Piece (Knight/Bishop).
Exchange Sacrifice: Voluntarily sacrificing a Rook for a Minor Piece (Knight/Bishop) to gain a strategic or positional advantage.
Exchange Variation: An opening variation where an early exchange of pawns or pieces occurs to clarify the position.
Expert: A title used to denote a player with a rating below master level (usually 2000-2199 USCF/FIDE).

F

Fianchetto: Developing a Bishop to b2 or g2 (after moving the b/g pawn) to control the long diagonal.
FIDE: The International Chess Federation (Fédération Internationale des Échecs). The governing body of global chess.
FIDE Master (FM): A chess title ranking below International Master but above Candidate Master, usually requiring a 2300 rating.
Fifty-Move Rule: A draw can be claimed if 50 moves pass without a pawn move or a capture.
File: A vertical column on the chessboard (labeled a-h).
Flag: To run out of time on the clock. "I flagged him" means I won on time. Refers to the physical flag on old analog clocks.
Fool's Mate: The fastest possible checkmate (2 moves), occurring if White plays 1. f3 and 2. g4 against Black's ...e5 and ...Qh4#.
Forced Move: A move that a player must make because all other moves lead to immediate loss or are illegal (e.g., getting out of check).
Fork: A tactic where one piece attacks two or more enemy pieces simultaneously. Knights are famous for forking.
Fortress: A defensive setup in the endgame that the opponent cannot break through, salvaging a draw despite being down material.

G

Gambit: An opening where material (usually a pawn) is sacrificed for rapid development or attack (e.g., King's Gambit, Evans Gambit).
Good Bishop: A bishop that is not blocked by its own pawns and is free to control active diagonals.
Grandmaster (GM): The highest title in chess, awarded by FIDE for achieving a 2500 rating and three "norms."
Greek Gift: The classic sacrifice Bxh7+, exposing the enemy King to a mating attack.

H

Hanging: Slang for leaving a piece unprotected and en prise (ready to be captured for free).
Hedgehog: A solid pawn structure (pawns on e6, d6, b6, a6) that is hard to break and stores up potential energy.
Hole: A square that can no longer be defended by pawns. It is a permanent weakness that enemies can occupy.
Hypermodernism: A school of chess theory that prefers controlling the center from a distance with pieces (e.g., Fianchetto) rather than occupying it immediately with pawns.

I

Imbalance: Any difference between the White and Black position (e.g., Bishop vs Knight, Space vs Structure). Imbalances dictate the plan.
Increment: Time added to the clock after every move (e.g., "3 minutes + 2 seconds increment").
Initiative: The momentum of the game. The player with the initiative is making threats that force the opponent to react.
Insufficient Material: A draw declared when neither side has enough pieces to force a mate (e.g., King vs King, or King+Knight vs King).
Interference: A tactical theme where a piece is sacrificed or moved to block the line of defense between two enemy pieces.
Intermezzo: See Zwischenzug.
International Master (IM): A strong FIDE title below Grandmaster, requiring a 2400 rating and norms.
Isolated Pawn (IQP): A pawn that has no friendly pawns on the adjacent files. It can be a dynamic strength in the middlegame but a static weakness in the endgame.

J

J'adoube: French for "I adjust." You must say this before touching a piece if you only intend to center it, to avoid the "Touch-Move" rule.

K

Key Square: A square in a pawn endgame that guarantees a win if the King occupies it (often related to Opposition).
Kibitzer: A spectator who offers (often unwanted) advice. In online chess, "Kibitzing" refers to chat analysis by spectators.
King: The most important piece. The game is lost if the King is checkmated.
King Hunt: A sustained attack that chases the enemy King across the board, usually ending in mate.
King Safety: The concept of keeping the King secure, usually by castling early and keeping pawn shields intact.
Kingside: The half of the board where the King starts (files e, f, g, h).
Knight: The piece that moves in an "L" shape and can jump over other pieces. Excellent in closed positions and for forking.

L

Liquidation: Trading off pieces to clarify the position, often to transition into a won Pawn Endgame.
Long Diagonal: The two longest diagonals on the board: a1-h8 and h1-a8.
Lucena Position: The "Building a Bridge" technique. Essential knowledge for winning Rook & Pawn endgames.
Luft: German for "Air." Moving a pawn in front of the castled King to create an escape square and prevent back-rank mate.

M

Major Piece: Rooks and Queens. Also called "Heavy Pieces."
Maróczy Bind: A pawn structure (pawns on c4 and e4) that clamps down on Black's d5 break, cramping Black's position.
Mate: Short for Checkmate.
Mating Net: A position where pieces cooperate to cut off all escape squares for the King, making checkmate inevitable.
Material: The total value of pieces on the board. (Pawn=1, Knight/Bishop=3, Rook=5, Queen=9).
Middlegame: The combat phase after the opening. Plans are formed, tactics occur, and pieces are maneuvered.
Miniature: A decisive game lasting fewer than 20-25 moves.
Minor Piece: Bishops and Knights (value approx 3 points).
Minority Attack: Advancing fewer pawns against a pawn majority (e.g., 2 vs 3) to create a weakness (often in the Carlsbad structure).
Mysterious Rook Move: A move by Nimzowitsch where a Rook moves to a closed file to discourage the opponent from opening it later.

N

Norm: A high-performance result in a tournament that counts toward the IM or GM title.
Notation: The system of writing down moves (e.g., 1. e4 e5). See How to Keep Score.
Novelty: A new move played in a known opening position (Theory) that hasn't been seen in master play before.

O

Open File: A file with no pawns. Rooks belong on open files!
Opening: The first phase of the game (approx moves 1-10). See our Repertoire Guide.
Opposite-Colored Bishops: A situation where each player has one bishop on different colors (e.g., Light vs Dark). It favors the attacker in middlegames but favors a draw in endgames.
Opposition: A crucial endgame concept where Kings face each other. The player who *doesn't* have to move "has the opposition" and can force the enemy King back.
Outpost: A secure square in enemy territory supported by a pawn, which cannot be attacked by enemy pawns. Knights love outposts.
Outside Passed Pawn: A passed pawn on the wing (a or h file) that distracts the enemy King, often allowing the main army to clean up the center.
Overloading: A tactic where a defensive piece has too many jobs to do. Distracting it causes the defense to crumble.
Overprotection: A strategic concept (popularized by Nimzowitsch) of defending a strong point more times than strictly necessary to free up pieces for other duties.

P

Passed Pawn: A pawn with no enemy pawns ahead of it or on adjacent files. It is a candidate to promote to a Queen.
Patzer: German slang for a weak or bungling chess player ("fish").
Pawn: The foot soldier of chess. "Pawns are the soul of chess" (Philidor).
Pawn Chain: A diagonal line of pawns protecting each other. The base of the chain is the weak point.
Pawn Island: A group of connected pawns separated from others. Having fewer pawn islands is generally better for the endgame.
Pawn Storm: Advancing multiple pawns on one wing to attack the enemy King (e.g., in the Sicilian Defense or King's Indian).
Perpetual Check: Forcing a draw by checking the enemy King endlessly, when there is no checkmate but the King cannot escape the checks.
Philidor Position: The "Gold Standard" defensive technique in Rook endings to secure a draw against a pawn.
Piece: Technically refers to non-pawns (Knights, Bishops, Rooks, Queens, King). Informally, any man on the board.
Pin: A tactic where a piece cannot move because it would expose a more valuable piece behind it (Absolute Pin = King behind; Relative Pin = Queen/Rook behind).
Poisoned Pawn: A pawn (often on b2/b7) that is free to take but taking it leads to dangerous complications or traps.
Positional Play: Improving your position gradually through structure, space, and piece activity, rather than immediate tactics.
Premove: An online chess feature where you input your move during your opponent's turn. It takes 0.1 seconds off your clock.
Promotion: When a pawn reaches the 8th rank, it transforms into a Queen, Rook, Bishop, or Knight.
Prophylaxis: The art of preventing your opponent's plans before they happen. "Thinking about what they want to do."

Q

Queen: The most powerful piece. It combines the movement of Rook and Bishop.
Queening: Promoting a pawn to a Queen.
Queenside: The half of the board where the Queen starts (files a, b, c, d).
Quiet Move: A move that is not a check or capture, but creates an inescapable threat (often stronger than a check).

R

Rank: A horizontal row on the chessboard (labeled 1-8).
Rapid Chess: A time control longer than Blitz but shorter than Classical (e.g., 15 to 30 minutes). The "sweet spot" for improvement.
Rating: A numerical value indicating skill. Beginners often start around 400-800; Masters are 2200+.
Refutation: Demonstrating that a move, opening, or combination is incorrect.
Resignation: Conceding defeat before being checkmated. Considered polite if the position is hopelessly lost.
Romantic Chess: The style of chess from the 19th century (Anderssen, Morphy) characterized by wild gambits, sacrifices, and attacking play.
Rook: A major piece that moves in straight lines. Rooks are powerful in the endgame and on open files.
Rook Lift: Moving a Rook forward (e.g., to the 3rd rank) to transfer it to an attack on the other side of the board.

S

Sacrifice: Voluntarily giving up material (Pawn, Exchange, or Piece) to gain a tactical or strategic win.
Scholar's Mate: The 4-move checkmate targeting f7. A classic trap for beginners.
Second: An assistant to a top player (like in the World Championship) who helps with opening preparation.
Semi-Open File: A file where you have no pawns, but your opponent does. It is a target for Rooks to attack the enemy pawn.
Sharp: A position full of tactical possibilities where a single mistake can lose the game instantly. The opposite of "Quiet."
Simul: Simultaneous Exhibition. An event where one strong player (often a master) plays multiple games against different opponents at the same time.
Skewer: A "Reverse Pin." Attacking a valuable piece which must move, exposing a less valuable piece behind it to capture.
Smothered Mate: A spectacular mate by a Knight where the King is surrounded ("smothered") by its own pieces and cannot move.
Sofia Rules: Tournament rules forbidding draw offers before a certain move number (usually move 30) to encourage fighting chess.
Space: The amount of territory (squares) controlled by a player. A space advantage allows for greater mobility.
Spite Check: A useless check given by a losing player just to prolong the game for one more move.
Stalemate: A draw where the player to move has no legal moves but is NOT in check. A common way to save a lost game.
Stem Game: The original game that introduced a specific opening variation.
Strategy: Long-term planning (pawn structure, bad bishops) as opposed to short-term tactics.
Swiss System: The most common tournament format where winners play winners, and losers play losers, without eliminating anyone.
Swindle: A trick or trap used by a player in a losing position to turn the tables or achieve a draw.
Symmetry: When Black copies White's moves. Usually dangerous for Black as White moves first and strikes first.

T

Tabiya: A standard position in an opening that is reached frequently, from which the real game and deviation from theory begins.
Tactics: Short-term sequences of moves (forks, pins, skewers) that result in immediate material gain or mate.
Tempo: Time in terms of moves. "Gaining a tempo" means developing a piece while forcing the opponent to waste a move defending.
Theoretical Draw: An endgame known to be a draw with perfect play (e.g., King+Bishop vs King), regardless of how much time is left.
Threefold Repetition: A draw occurs if the exact same position (same player to move, same legal moves) appears on the board three times.
Time Control: The rules regarding time (e.g., 90 minutes for 40 moves). See our guide on Blitz vs Rapid vs Bullet.
Time Trouble: Having very little time left on the clock (e.g., under 1 minute), which often leads to blunders.
Touch-Move Rule: If you touch a piece in an OTB tournament, you MUST move it (if legal). If you touch an enemy piece, you must capture it.
Transposition: Reaching a standard opening position via a different move order (e.g., reaching a French Defense from a Queen's Pawn opening).
Trap: A move that encourages the opponent to make a natural-looking response that actually loses material or leads to mate.
Triangulation: A King maneuver in the endgame used to lose a tempo and pass the move to the opponent while maintaining the same position (forcing Zugzwang).

U

Undermining: A tactic of capturing or driving away a defending piece (often a pawn) to leave a target vulnerable.
Underpromotion: Promoting a pawn to a Knight, Rook, or Bishop instead of a Queen (usually to avoid stalemate or deliver a checkmate).

V

Variation: A specific sequence of moves that differs from the main line of an opening or analysis.

W

Waiting Move: A move made with the intention of doing nothing significant, forcing the opponent to move and potentially weaken their position.
Weakness: A pawn or square that is difficult to defend and can be exploited.
White: The player who moves first in a game of chess. White pieces are light-colored.
Windmill: A devastating tactic (usually involving a Rook and Bishop) involving repeated discovered checks to win massive material.
Wing: The flanks of the board (the a-, b-, c- files on the Queenside and f-, g-, h- files on the Kingside).
Woodpusher: Derogatory slang for a weak chess player who plays without a plan, just "pushing wood."

X

X-Ray: An indirect attack or defense where a piece exerts influence through another piece (friend or foe) occupying a square on the same line.

Z

Zugzwang: A German term meaning "compulsion to move." A situation where every legal move available to a player worsens their position.
Zwischenzug: German for "intermediate move." An unexpected move inserted into a tactical sequence (usually a check or capture) that changes the outcome.

This glossary covers the most important terms. For in-depth guides on openings, strategies, and famous games, please explore the rest of our Chess Strategy sections.