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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 category below to filter the list.

Showing all terms

A B C D E F G H I J K L M N O P Q R S T U V W X Z

A

Absolute Pin: A powerful tactical situation where a piece shields the King from an attack. The pinned piece is legally forbidden from moving.
Advantage: Having a better position than your opponent (e.g., "White has a space advantage" or "Black has a material advantage").
Adjudication: The process of a chess arbiter determining the result of an unfinished game based on the position.
Adjournment: The temporary suspension of a game to be continued later. Rare in modern play.
Alekhine, Alexander: The 4th World Champion. Known for complex tactical attacks and deep combinations.
Alekhine's Gun: A powerful triple battery where a Queen lines up behind two Rooks on the same file.
Algebraic Notation: The standard method for recording chess moves (e.g., e4, Nf3).
Anand, Viswanathan: The 15th World Champion. The "Madras Tiger," famous for his rapid calculation speed.
Anastasia's Mate: A geometric checkmate where a Knight traps the King against the board edge while a Rook delivers mate on the open file.
Annotation: Commentary, notes, and analysis added to a recording of a game.
Arbiter: The referee of a chess tournament responsible for enforcing rules.
Armageddon: A tie-break game where White has more time but must win; Black wins if drawn.
Arabian Mate: A classic checkmate pattern delivered by a Rook and Knight working in unison to trap the King in a corner.
Artificial Castling: Manually moving the King and Rook over several turns to achieve a castled position.
Attack: An aggressive action attempting to capture a piece, checkmate the King, or create weaknesses.
Attraction: A tactical motif where you force or lure an opponent's piece onto a vulnerable square.

B

Back Rank: The first or eighth rank. A weak back rank can lead to checkmate.
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.
Bad Bishop: A bishop restricted by its own pawns reducing its mobility.
Battery: A formation where two or more pieces line up on the same line to multiply their power.
Bishop: A Minor Piece that moves diagonally. Value: 3.
Bishop Pair: Possessing both bishops in an open position is often an advantage.
Black: The player who moves second. The pieces are usually dark-colored (Dark Brown or Black). (See Board Setup »)
Blindfold Chess: Playing chess without looking at the board.
Blind Swine Mate: A checkmate pattern where two rooks invade the 7th rank.
Blitz: Fast chess! Typically 3 to 5 minutes per player.
Blockade: Placing a piece directly in front of an enemy passed pawn to stop it.
Blunder: A severe mistake that loses material or the game immediately. Worse than a "Mistake".
Board Geometry: The board has 64 squares, organized into Ranks (rows), Files (columns), and Diagonals.
Board Setup: The standard arrangement of pieces at the start of the game. Remember: "White on right". (Read Full Guide »)
Botvinnik, Mikhail: The 6th World Champion. The patriarch of the Soviet Chess School and pioneer of scientific preparation.
Brilliancy: A game containing a beautiful, original, and correct strategic concept.
Bullet Chess: Ultra-fast chess! Typically 1 minute or less per player.

C

Calculation: Mentally visualizing future moves.
Capablanca, José Raúl: The 3rd World Champion. A Cuban genius known for his endgame mastery and "machine-like" precision.
Candidate Master (CM): A FIDE title ranking below FIDE Master.
Candidate Move: A shortlist of moves you consciously evaluate before making a decision.
Capture: Taking an opponent's piece by moving onto its square. The enemy piece is removed.
Carlsen, Magnus: The 16th World Champion. Renowned for his universal style and endgame grinding ability.
Castling: The only move where two pieces move at once (King and Rook) to get the King to safety. (Read Full Guide »)
Center: The critical squares e4, d4, e5, and d5.
Centralization: Bringing pieces towards the center where they control the most squares.
Check: The king is under immediate attack and must be protected.
Checkmate: The ultimate goal of the game: the King is under attack ("in check") and has no legal move to escape. The game ends immediately. (See many Classic Examples »)
Classical Chess: Standard slow chess (e.g., 90+ minutes per player).
Clearance Sacrifice: A piece moves to vacate a key square or open a line for a stronger piece.
Clock: The timer used to limit how long each player can think. Your time counts down on your turn; after you move, you press the clock to start your opponent’s time. If your time reaches zero, you usually lose (you “get flagged”).
Closed Game: A position with locked pawn chains where lines are blocked.
Combination: A long, forced sequence of moves (usually involving a sacrifice) to win material or mate. Distinct from a simple 1-2 move "Tactic".
Compensation: Strategic advantages gained in return for sacrificing material.
Connected Pawns: Pawns on adjacent files that can protect each other.
Correspondence Chess: Games played over days or weeks per move.

D

Dark Square Complex: A situation where a player is weak on dark squares.
Declined (Gambit): Refusing a gambit pawn offered by the opponent (e.g., Queen's Gambit Declined).
Defend: Preventing an opponent’s threat by protecting a piece, square, or King.
Decoy: Luring an opponent’s piece onto a specific square to make it vulnerable.
Deflection: Forcing a key defending piece away from an important square.
Desperado: A doomed piece that sacrifices itself for maximum damage.
Development: Moving pieces from the back rank to active squares. "Ahead in development" means having more active pieces.
Diagonal: A straight line of squares of the same color running at an angle.
Ding Liren: The 17th World Champion. Known for his stoic defense and resilience under pressure.
Discovered Attack: The revealed piece delivers an attack.
Discovered Check: A powerful variant where the revealed piece delivers a check.
Double Attack: A simultaneous attack on two targets.
Double Check: A check delivered by two pieces at the same time. The King MUST move.
Doubled Pawns: Two pawns of the same color on the same vertical file.
Draw: A game where neither player wins. Common draws include Stalemate, Threefold Repetition, the 50-move rule, and Draw by Agreement. (See the 6 Draw Rules »)
Draw by Agreement: When both players agree to end the game as a tie.

Draw Offer

An offer to end the game as a draw, which the opponent may accept or decline.

E

Elo Rating: The system used to calculate the relative skill level of chess players.
Endgame: The final phase of the game where few pieces remain.
Engine: Computer software (like Stockfish) used to analyze games.
En Passant: A special pawn capture rule: "In passing." (Read Full Guide »)
En Prise: A piece left hanging or unprotected.
Euwe, Max: The 5th World Champion. A Dutch mathematician who defeated Alekhine using logic and preparation.
Exchange: Trading pieces.
Exchange Sacrifice: Sacrificing a Rook for a Minor Piece to gain an advantage.
Exchange Variation: An opening variation where an early exchange of pawns occurs.
Expert: A player with a rating below master level (2000-2199).

F

Fianchetto: Developing a Bishop to b2 or g2 to control the long diagonal.
FIDE: The International Chess Federation.
FIDE Master (FM): A chess title ranking below FIDE Master.
Fifty-Move Rule: A draw claim if 50 moves pass without a pawn move or capture.
File: A vertical column of squares on the chessboard, lettered a through h. (See Board Diagram »)
Fischer, Bobby: The 11th World Champion. An American legend known for his clarity, willpower, and the 1972 Match of the Century.
Flag: To run out of time on the clock.
Fool's Mate: The fastest possible checkmate (2 moves).
Forcing Move: A move that limits the opponent's responses: Checks, Captures, Threats.
Forced Move: A move that must be made because all other moves are illegal.
Fork: A tactic where one piece attacks two or more enemy pieces simultaneously.
Fortress: A defensive setup in the endgame that the opponent cannot break through.

G

Gaining Space: Advancing pawns (and pieces) to control more of the board than the opponent.
Gambit: Sacrificing material for rapid development or attack.
Good Bishop: A bishop that is not blocked by its own pawns.
Grandmaster (GM): The highest title in chess.
Greek Gift: The classic sacrifice Bxh7+, exposing the enemy King.

H

Hanging: Leaving a piece unprotected.
Hedgehog: A solid pawn structure (pawns on e6, d6, b6, a6).
Hole: A square that can no longer be controlled by pawns.
Hypermodernism: Controlling the center from a distance with pieces rather than pawns.

I

Illegal Move: A move not permitted by the rules (e.g., moving King into check). Online it is blocked; OTB it incurs penalties.
Imbalance: Any difference between the White and Black position.
Increment: Time added to the clock after every move.
Initiative: The momentum of the game; making threats that force the opponent to react.
Insufficient Material: A draw declared when neither side has enough pieces to force a mate.
Interference: Sacrificing a piece to block the line of defense between two enemy pieces.
Intermezzo: See Zwischenzug.
International Master (IM): A strong FIDE title below Grandmaster.
Isolated Pawn (IQP): A pawn that has no friendly pawns on the adjacent files.

J

J'adoube: French for "I adjust." Said before adjusting a piece.

K

Karpov, Anatoly: The 12th World Champion. The master of prophylaxis and positional restriction ("The Boa Constrictor").
Kasparov, Garry: The 13th World Champion. Dominant for 20 years with an aggressive, dynamic style and deep opening prep.
Key Square: A square in a pawn endgame that guarantees a win if occupied.
Kibitzer: A spectator who offers advice.
King: The most important piece.
King Hunt: Forcing the King out of safety and attacking it across the board.
King Safety: Keeping the King secure, usually by castling.
Kingside: The half of the board where the King starts (e, f, g, h).
Knight: The piece that moves in an "L" shape.
Kramnik, Vladimir: The 14th World Champion. Defeated Kasparov with the "Berlin Wall" and deep positional understanding.

L

Lasker, Emanuel: The 2nd World Champion. Held the title for 27 years; a pioneer of psychological chess.
Legal Move: A move allowed by the rules. You cannot move a pinned piece or move your King into check.
Light-Squared / Dark-Squared: Refers to the color of the squares or the Bishops that travel on them.
Liquidation: Trading off pieces to clarify the position, often to reach an endgame.
Long Diagonal: a1-h8 and h1-a8.
Loose Piece: A piece that is undefended. "Loose pieces drop off" (LPDO).
Lucena Position: The "Building a Bridge" technique for winning Rook endgames.
Luft: Creating an escape square for the King ("Air").

M

Major Piece: Collective term for Queens and Rooks. These are the "heavy" pieces capable of checkmating a lone King. (Read Definition »)
Maróczy Bind: A pawn structure (c4 and e4) that cramps Black.
Mate: Short for Checkmate. It occurs when a King is attacked and cannot escape. (See Checkmate Patterns »)
Mate in 1 / Mate Threat: A position where you can deliver checkmate on your very next move.
Mating Net: Pieces cooperating to cut off escape squares for the King.
Material: Refers to the pieces and pawns on the board and their relative value (Pawn=1, Knight/Bishop=3, Rook=5, Queen=9). Having more "material" usually means you are winning. (See Piece Values »)
Middlegame: The combat phase after the opening.
Miniature: A game lasting fewer than 25 moves.
Minor Piece: Collective term for Bishops and Knights (Value: ~3 points). Unlike Major Pieces, a single Minor Piece is not strong enough to checkmate a lone King. (See Movement & Rules »)
Mistake: A bad move, but not as catastrophic as a Blunder. Often loses a small advantage.
Minority Attack: Advancing fewer pawns against a pawn majority to create a weakness.
Mysterious Rook Move: A move to a closed file to discourage the opponent from opening it.

M

Minority Attack: Advancing fewer pawns against a pawn majority to create a weakness.
Mysterious Rook Move: A move to a closed file to discourage the opponent from opening it.

N

Norm: A high-level tournament result counting toward a title (IM or GM).
Notation: Writing down moves.
Symbols: x (captures), + (check), # (checkmate), O-O (short castle).
Novelty: A new move in a known opening position.

O

Open File: A file with no pawns. Rooks love open files!
Opening: The first phase of the game (approx first 10-15 moves). Goal: Develop pieces and control the center.
Opening Principles: Basic guidelines for the opening: develop pieces, control the center, and safeguard the King.
Opposite-Colored Bishops: Bishops on different colors. Favors attacker in middlegame, draws in endgame.
Opposition: Kings facing each other in the endgame; forcing the enemy King to move.
Outpost: A strong square (usually protected by a pawn) where a piece cannot be driven away by enemy pawns.
Outside Passed Pawn: A passed pawn on the wing that distracts the enemy King.
Overloading: A piece having too many defensive jobs at once.
Overprotection: Defending a strong point more times than strictly necessary.

P

Passed Pawn: A pawn with no enemy pawns ahead of it on the same or adjacent files.
Patzer: Slang for a weak player.
Pawn: The foot soldier. Value: 1.
Pawn Chain: A diagonal line of pawns protecting each other.
Pawn Island: A group of connected pawns separated from others.
Pawn Storm: Advancing pawns on one wing to attack the enemy King.
Pattern Recognition: Instantly spotting familiar tactics without calculating.
Perpetual Check: Forcing a draw by checking the King endlessly. (See Threefold Repetition).
Petrosian, Tigran: The 9th World Champion. "Iron Tigran," famous for his impenetrable defense.
Philidor Position: The standard defensive technique to draw Rook endings.
Piece: Usually refers to non-pawns (Knight, Bishop, Rook, Queen, King).
Piece Movement: The rules governing how the King, Queen, Rook, Bishop, Knight, and Pawn move. (Read Full Guide »)
Pin: A piece cannot move because it exposes a more valuable piece behind it.
Poisoned Pawn: A pawn that is left unguarded but is dangerous to capture.
Positional Play: Improving position gradually through structure and activity rather than immediate tactics.
Premove: Inputting a move during the opponent's turn (online only).
Promotion: When a pawn reaches the opposite side of the board (8th rank), it transforms into a Queen, Rook, Bishop, or Knight. (Read Full Guide »)
Prophylaxis: A move that prevents the opponent's future plans.
Protected / Defended: A piece is safe because if captured, you can capture back.

Q

Queen: The most powerful piece. Value: 9.
Queening: Promoting a pawn to a Queen.
Queenside: Files a, b, c, d (the left side for White).
Quiet Move: A non-checking move that creates an inescapable threat.

R

Rank: A horizontal row of squares on the chessboard, numbered 1 to 8. (See Board Diagram »)
Rapid Chess: Time control longer than Blitz (e.g., 10-30 mins per player).
Rating: A number indicating skill level (e.g., 1200).
Relative Pin: A pin where moving is legal but loses material.
Removing the Defender: Capturing or distracting a piece that defends a key target.
Refutation: Proving a move or idea is incorrect.
Resignation: Choosing to end the game and admit defeat before checkmate occurs. (How Games are Won »)
Romantic Chess: 19th-century style of attacking, sacrificial chess.
Rook: A major piece moving in straight lines. Value: 5.
Rook Lift: Moving a Rook forward to attack on the flank.

S

Sacrifice: Giving up material (e.g., a Knight) to gain an attack.
Scholar’s Mate: A 4-move checkmate attacking f7.
Second: An assistant to a top player.
Semi-Open File: A file with opponent's pawns but none of your own.
Sharp: A risky, tactical position where accuracy is critical.
Simplify: Trading pieces to reach a favorable endgame (also see Liquidation).
Simul: A master playing multiple games at once.
Skewer: Attacking a valuable piece to win the piece behind it (Reverse Pin).
Smothered Mate: A Knight mate where the King is blocked in by its own pieces.
Smyslov, Vasily: The 7th World Champion. Known for his harmonious style.
Sofia Rules: Tournament rules forbidding early draw offers.
Space: The number of squares your pawns and pieces control. "Gaining Space" restricts the opponent's mobility.
Spassky, Boris: The 10th World Champion. A universal player.
Spite Check: A useless check by a losing player that delays the game but changes nothing.
Square: One of the 64 spaces on the chessboard.
Stalemate: A specific type of draw where the player to move has no legal moves but is NOT in check. (See Examples »)
Steinitz, Wilhelm: The 1st World Champion. The father of modern positional chess theory.
Stem Game: The game that introduced an opening variation.
Strategy: Long-term planning (pawns, weak squares, bad pieces).
Swiss System: A common tournament format where players with similar scores play each other.
Swindle: A trick to save a lost position.
Symmetry: When Black copies White's moves.

T

Tabiya: A standard opening position.
Tactics: Short-term sequences (like Forks or Pins) for immediate gain. Distinct from Strategy (long-term).
Tal, Mikhail: The 8th World Champion. "The Magician from Riga," famous for intuitive sacrifices.
Tempo: Time measured in moves. "Gaining a tempo" means developing a piece while forcing the opponent to waste a turn.
Theoretical Draw: An endgame known to be a draw with perfect play.
Threat: A move that intends to do damage on the next turn.
Threefold Repetition: A draw can be claimed if the exact same position occurs three times. (Read Full Rule »)
Time Control: The rules regarding clock time.
Time Trouble: Having very little time left.
Touch-Move Rule: If you touch a piece, you must move it.
Trade: Swapping pieces of equal value. (See Exchange).
Transposition: Reaching a position via a different move order.
Trap: A move that provokes an error.
Trapping: Surrounding a piece so it has no escape.
Triangulation: A King maneuver to lose a tempo and force Zugzwang.

U

Undermining: Removing the guard or weakening the base of a pawn chain.
Underpromotion: Promoting a pawn to a Knight, Rook, or Bishop instead of a Queen. Used to deliver surprise checkmates or avoid stalemate. (See Famous Examples »)

V

Variation: A specific sequence of opening moves.

W

Waiting Move: A move intended to pass the turn without changing the position.
Weakness: A pawn or square difficult to defend.
White: The player who moves first. The pieces are usually light-colored (White or Light Wood). (See First Move Rule »)
Windmill: A pattern of repeated discovered checks.
Wing: The flanks of the board.
Winning on Time: Winning the game because your opponent's clock reaches zero. (Read Rules »)
Woodpusher: Slang for a weak, planless player.

X

X-Ray Attack: Attacking a square "through" another piece.

Z

Zugzwang: "Compulsion to move." Any move worsens your position.
Zwischenzug: "Intermediate move." An unexpected move inserted into a sequence.

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.