Chess glossary
Every essential chess term, explained simply and sorted alphabetically.
A
- Active king
- A king brought toward the center or the front in the endgame, becoming a full offensive piece rather than one to merely protect.
- Algebraic notation
- The standard system for recording moves and squares on the board (e.g. Nf3, e4). Read more →
- Anastasia's mate
- A checkmate where a knight and a rook trap the enemy king against the edge of the board. Read more →
- Arabian mate
- A checkmate delivered by a rook and a knight that trap the enemy king in a corner of the board. Read more →
B
- Back-rank mate
- A checkmate where the king, boxed in by its own pawns on the last rank, is mated by a rook or queen. Read more →
- Backward pawn
- A pawn that has fallen behind its neighbors and can no longer be supported by another pawn. Read more →
- Battery
- Two pieces lined up on the same rank, file, or diagonal, combining their attacking power in the same direction.
- Bishop pair
- Keeping both bishops, which together cover the light and dark squares: often considered a small positional advantage.
- Blindfold chess
- Playing without seeing the board or the pieces, visualizing the entire game mentally.
- Blitz
- A fast time control, usually between 3 and 10 minutes per player for the whole game. Read more →
- Boden's mate
- A checkmate where two bishops, on crossing diagonals, trap a castled enemy king. Read more →
- Buchholz
- A tiebreak criterion that adds up the total scores of a player's opponents: the better their opponents did, the higher their Buchholz.
- Bye
- A point (or half-point) awarded to a player with no opponent in a given round, due to an odd number of participants.
C
- Castling
- A special move shifting the king and a rook at once, to bring the king to safety and develop the rook. Kingside castling (O-O) is faster and generally safer; queenside castling (O-O-O) is slower to prepare but brings the rook closer to the center. Read more →
- Center
- The d4, d5, e4, and e5 squares, whose control is a major strategic goal in the opening.
- Check
- The king is under direct attack and can be captured on the next move if left unprotected.
- Checkmate
- The king is in check with no legal move available to escape the threat: the game ends immediately.
- Chess clock
- The dual-display clock used in competition to time each player's thinking time.
- Chessboard
- The 64-square (8x8) board, alternating light and dark squares, on which the game is played.
- Combination
- A forced sequence of moves, often involving a sacrifice, that leads to a concrete gain: material, mate, or a decisive advantage.
- Correspondence chess
- A form of chess where moves are exchanged remotely (once by mail, now usually online), with several days of thinking time per move.
D
- Damiano's mate
- A checkmate achieved by sacrificing the queen to force the enemy king into a corner, then delivering mate with a rook. Read more →
- Development
- The process of bringing pieces out from their starting squares to make them active.
- Discovered check
- A check revealed by moving a piece that was blocking another piece's attack on the enemy king. Read more →
- Double check
- A check delivered by two pieces at once, usually via a discovered attack: the king must move, since blocking or capturing can't stop both attackers.
- Doubled pawns
- Two pawns of the same side stacked on the same file, usually a structural weakness. Read more →
- Draw
- A game result where neither player wins: by mutual agreement, stalemate, insufficient material, position repetition, or the fifty-move rule. Read more →
E
- Elo rating
- The numeric rating system measuring a player's relative strength, based on their results. Read more →
- En passant
- A special rule allowing a pawn to capture an enemy pawn that just advanced two squares, as if it had only moved one. Read more →
- Epaulette mate
- A checkmate where the enemy king is boxed in by its own pieces standing on either side, like epaulettes, and mated by a queen. Read more →
- Exchange
- Capturing an enemy piece and being recaptured in turn by a piece of roughly equal value.
F
- FEN (Forsyth-Edwards Notation)
- A text notation system describing a full position in a single line (piece placement, side to move, castling rights, en passant target), for example "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1" for the starting position.
- Fianchetto
- Developing a bishop onto the long diagonal, on the square just in front of where its knight started (g2 or b2 for White, g7 or b7 for Black), after pushing the pawn in front of it one square.
- FIDE title (GM, IM, FM)
- The official titles awarded by FIDE based on level and results: Grandmaster (GM), International Master (IM), FIDE Master (FM), with their women's equivalents (WGM, WIM, WFM). Earned by achieving "norms" in qualifying tournaments. Read more →
- Fifty-move rule
- The game is drawn if 50 moves pass in a row with no capture and no pawn move. Read more →
- File
- A vertical line of the board, labeled with a letter from a to h.
- Fork
- A move that attacks two (or more) enemy pieces at once with the same piece. Read more →
- Fortress
- A defensive endgame setup where the weaker side locks the position down and blocks all enemy progress, despite a material deficit that would look decisive on paper. Read more →
- French Defense
- A solid reply to 1.e4 where Black plays 1...e6 then usually 2...d5, building a stable pawn chain at the cost of a light-squared bishop that's often locked in. Read more →
G
- Gambit
- An opening where material, often a pawn, is voluntarily sacrificed to gain time or space. Read more →
H
- Half-open file
- A file where only one side still has a pawn. Read more →
- Hanging
- A piece is "hanging" when it can be captured for free by the opponent.
I
- Initiative
- The advantage of dictating the pace of the game by forcing the opponent to react to threats.
- Interference
- Placing a piece on an enemy piece's line of action to cut its connection to another piece or square it was defending.
- Isolated pawn
- A pawn with no friendly pawn on either neighboring file to support it. Read more →
- Italian Game
- One of the oldest openings, starting with 1.e4 e5 2.Nf3 Nc6 3.Bc4. Read more →
L
- Légal's mate (Légal's trap)
- An opening trap where the queen is sacrificed to deliver a quick mate against an opponent who carelessly pinned a knight. Read more →
- Losing castling rights
- Permanently losing the right to castle, usually by moving the king or the relevant rook before castling.
M
- Mating with bishop and knight
- An endgame technique driving the lone enemy king into the corner matching the bishop's square color: considered the hardest basic checkmate to execute. Read more →
- Mating with queen and king
- A basic endgame technique of driving the lone enemy king to the edge of the board with the queen, supported by your own king. Read more →
- Mating with two bishops
- An endgame technique driving the lone enemy king into a corner using two bishops working on complementary diagonals. Read more →
- Miniature
- A short, decisive game, typically finished in under 20 moves.
- Move (to move)
- Whose turn it is to play: being "to move" means it's that player's turn.
N
- Norm
- A result achieved in a qualifying tournament that counts toward earning a FIDE title (GM, IM, FM): usually three are needed to earn a title.
O
- Open (tournament)
- A tournament open to any registered player regardless of level or title, usually run using the Swiss system.
- Open file
- A file with no pawns on it at all, ideal for placing a rook. Read more →
- Opposition
- A face-off between the kings in an endgame where the player NOT to move controls the outcome. Read more →
- Outpost
- An advanced weak square in the opponent's territory, typically occupied by a knight that no pawn can chase away. Read more →
P
- Pairing
- The process that determines, in each round of a tournament, which player faces which opponent, following a set method (Swiss system, round-robin...).
- Passed pawn
- A pawn that no enemy pawn can stop anymore on its way to promotion. Read more →
- Pawn endgame
- An endgame with only kings and pawns left, where opposition and square-counting are often decisive.
- Pawn majority
- A numerical pawn advantage on one wing of the board (e.g. 3 against 2), often used to create a passed pawn in the endgame.
- Perpetual check
- A series of checks the defending side can neither block nor escape: the game is drawn, since the side in danger saves itself by checking without interruption.
- PGN (Portable Game Notation)
- The standard file format for recording and sharing a complete game, move by move, for example "1.e4 e5 2.Nf3 Nc6 3.Bb5" for the start of a Ruy Lopez.
- Phases of the game
- The three main stages of a chess game: opening, middlegame, and endgame. Read more →
- Piece values
- The approximate point system (pawn = 1, knight/bishop = 3, rook = 5, queen = 9) used to evaluate material. Read more →
- Pin
- A piece is "pinned" when it cannot move without exposing a more valuable piece (or the king) behind it to attack. Read more →
- Plan
- A medium- or long-term strategic goal (attacking a weak pawn, opening a file, trading off bad pieces...) that guides move choices.
- Promotion
- A pawn reaching the last rank turns into a queen, rook, bishop, or knight, the player's choice.
- Prophylaxis
- Anticipating and preventing the opponent's plans before they even carry them out, for example playing a seemingly quiet move that pre-empts an enemy breakthrough.
Q
- Queen's Gambit
- A classical opening where White offers the c-pawn to gain central control after 1.d4 d5 2.c4. Read more →
R
- Resignation
- When a player gives up and concedes the game before checkmate, usually by tipping over their king or telling the arbiter.
- Rook endgame
- An endgame where each side has only one or more rooks left besides the king and pawns: the most common endgame type. Read more →
- Round
- One round of play in a tournament, where every player still in it plays a game.
- Round-robin
- A tournament format where every player faces every other participant exactly once.
- Ruy Lopez (Spanish Opening)
- The classical opening 1.e4 e5 2.Nf3 Nc6 3.Bb5, one of the most studied in chess history. Read more →
S
- Sacrifice
- Voluntarily giving up material to gain a positional, tactical advantage, or a decisive attack. Read more →
- Scholar's mate
- A four-move checkmate exploiting the poorly defended f7 pawn very early in the game. Read more →
- Sicilian Defense
- The most-played reply to 1.e4, where Black answers 1...c5 to unbalance the game. Read more →
- Simultaneous exhibition
- An exhibition where a (usually strong) player takes on several opponents at once, moving from board to board.
- Skewer
- An attack on a valuable piece that, once it moves, exposes a less valuable piece behind it on the same line. Read more →
- Smothered mate
- A knight checkmate where the enemy king is boxed in by its own pieces and cannot escape. Read more →
- Sonneborn-Berger
- A tiebreak criterion that weighs the result against each opponent by that opponent's final score, rewarding wins against the strongest finishers.
- Square rule
- A quick visual method to determine whether a king can catch up to an enemy passed pawn. Read more →
- Staircase mate
- A mating technique (also known as the "ladder mate") using two rooks, or a rook and a queen, advancing in alternation to push the enemy king to the edge. Read more →
- Stalemate
- The player to move is not in check but has no legal move available: the game is a draw. Read more →
- Strategy
- The long-term planning of a game: assessing the position's strengths and weaknesses to choose a coherent plan, as opposed to immediate tactical calculation.
- Study
- A composed, often artistic position where one side must find a unique path to a win or a draw against the opponent's best defense.
- Swiss system
- The most common tournament pairing system: each round, players with similar scores are paired against each other, with no elimination, until everyone has played the same number of rounds. Read more →
T
- Tactics
- Short-term combinations (forks, pins, sacrifices...) that exploit an immediate weakness, as opposed to long-term strategic plans.
- Tempo
- A unit of time in the game: "gaining a tempo" means forcing the opponent to lose a move.
- The exchange
- The value difference between a rook and a minor piece (bishop or knight): "winning the exchange" means getting a rook in return for a minor piece.
- The Opera mate
- A classic checkmate where a rook and a bishop combine to mate a king stuck in the center, popularized by a famous game played at the Paris Opera. Read more →
- Threat
- A move that, if left unanswered, would let the player win material or gain a decisive advantage on the next move.
- Threefold repetition
- The game is drawn if the same position occurs three times with the same player to move. Read more →
- Tiebreak
- The system used to determine a winner among players tied on points at the end of a tournament (rapid or blitz playoff games, or mathematical criteria like Buchholz).
- Time control
- The amount of thinking time allotted to each player for the whole game: blitz (under 10 minutes), rapid (10 to 60 minutes), or classical/standard (over 60 minutes).
- Trap
- A move that looks natural or tempting for the opponent, but hides a refutation or a threat they haven't anticipated.
U
- Underpromotion
- Choosing to promote a pawn to a rook, bishop, or knight instead of a queen, usually to avoid a stalemate or create a precise threat.
V
- Variation
- A specific sequence of moves within an opening, or an alternative line considered when analyzing a position.
W
- Weak square
- A square that can no longer be defended by any pawn, ideal for the opponent to permanently install a piece on. Read more →
- Wing
- Each half of the board on either side of the d/e files: the kingside (e- to h-files) and the queenside (a- to d-files).
Z
- Zeitnot (time trouble)
- The situation where a player has very little time left on the clock, forcing fast decisions at the risk of mistakes.
- Zugzwang
- A situation where a player would be better off not having to move at all: every available move worsens their position. Read more →
- Zwischenzug (in-between move)
- An unexpected move, often a threat, inserted before responding to the opponent's initial threat. Read more →