Every chess term explained in plain English.
Heard someone mention a zwischenzug, a fianchetto or hope chess and nodded along? Here are 197 terms covering the rules, tactics, checkmate patterns, strategy, endgames, openings, notation and the slang players use online, many with a board to show you exactly what they mean.
Try a shorter word, or a different spelling. Missing a term? Tell us at hello@chessicous.com.
Also: chess notation, SAN
The standard way to write chess moves: a piece letter (K, Q, R, B, N; nothing for pawns) plus the square it moves to, as in Nf3 or e4.
x marks a capture, + check, # checkmate, O-O and O-O-O castling, and =Q a promotion.
Blog: How to read chess notationAlso: Anastasia mate
A knight and a rook (or queen) trap the king on the edge of the board: the knight covers the escape squares while the rook mates along the file.
The name comes from a novel by Wilhelm Heinse in which the pattern appears.
Lesson: Anastasia’s & Arabian MatesA rook and knight mate a king in the corner: the rook checks from next door and the knight guards both the rook and the escape square. It is one of the oldest known mating patterns.
Lesson: Anastasia’s & Arabian MatesA tiebreak game that can’t be drawn: White gets more time, but a draw counts as a win for Black.
A player’s first rank: the 1st for White, the 8th for Black. A king stuck there behind its own pawns can be mated by a rook or queen.
Also: back rank mate, corridor mate
A rook or queen checkmates a king trapped on its first rank behind its own pawns.
Lesson: Back-Rank MateA pawn that has fallen behind its neighbors and can’t safely advance. The square in front of it often becomes an outpost for the opponent.
A bishop hemmed in by its own pawns fixed on squares of its color. It can still defend, but it has little scope.
Lesson: Good & Bad BishopsTwo pieces lined up on the same line, like a queen behind a bishop or two rooks on a file, so their power is doubled.
Also: two bishops
Having both bishops while the opponent doesn’t. Together they cover squares of both colors, which is a real advantage in open positions.
Fast chess with a few minutes per player. FIDE counts games with ten minutes or less each as blitz; online sites draw the lines a little differently.
Putting a piece directly in front of an enemy passed or isolated pawn to stop it moving. Knights are the classic blockaders.
Also: ??, blundered
A terrible mistake, like hanging your queen or missing mate in one. Annotated with ??. Everyone blunders; the trick is blundering less.
Blog: 10 common beginner mistakesAlso: Boden mate
Two bishops on criss-crossing diagonals mate a king, usually one that has castled queenside, with its own pieces blocking the way out.
Lesson: Boden’s, Greco’s & Légal’sAlso: Bongcloud Attack
The joke opening 1.e4 e5 2.Ke2, walking the king forward on move two. It breaks every opening principle, which is exactly the point.
Also: book
A move that is part of established opening theory. Game review marks these as “Book”.
Game reviewAlso: the box, shrinking the box
The standard way to mate with king and rook (or queen) vs king: use the rook to fence the enemy king into a box, then shrink the box until it is trapped on the edge.
Blog: How to checkmate with a king and rookA pawn sacrifice or series of pawn moves that smashes through the enemy pawns to create a passed pawn.
Lesson: Outside Pawns & BreakthroughsAlso: !!, brilliancy
The annotation !! marks a brilliant move: a strong, hard-to-find move, often a sacrifice. It is the highest praise a move can get.
Blog: What is a brilliant move?Very fast chess, usually with under three minutes per player for the whole game.
Also: Caro-Kann Defense
1.e4 c6 followed by …d5: like the French, but Black keeps the light-squared bishop free. Known for being solid.
Caro-Kann DefenseAlso: O-O, O-O-O, castle
A special move of the king and a rook together: the king moves two squares toward the rook, and the rook jumps to the square the king crossed.
You can’t castle if the king or that rook has moved, if any square between them is occupied, if you are in check, or if the king would pass through or land on an attacked square.
Lesson: CastlingThe four middle squares d4, e4, d5 and e5. Pieces in the center reach more squares, so both sides fight for it from move one.
Lesson: Control the CenterAlso: cp
One hundredth of a pawn, the unit engines use for evaluations. +150 centipawns is the same as +1.5.
Moving pieces, and in the endgame the king, toward the center where they control the most squares.
Also: cheap shot, cheap trap
A simple trap that only works if the opponent isn’t paying attention.
A king is in check when it is attacked. The player in check must get out of it immediately by moving the king, blocking, or capturing the attacker.
Lesson: Three Ways OutAlso: mate
Check that cannot be escaped. Checkmate ends the game immediately and the side that delivers it wins.
Lesson: Checkmate!Also: Fischer Random
A variant proposed by Bobby Fischer where the back-rank pieces are shuffled into one of 960 starting positions. Bishops stay on opposite colors and the king stays between the rooks so castling still works.
Because every game starts differently, memorized opening theory doesn’t help, and you have to think from move one.
Tool: Chess960Also: standard, slow chess
Slow chess with an hour or more per player. Most serious tournaments and title norms use classical time controls.
Moving a piece out of the way, often with tempo or as a sacrifice, to open a line or free a square for another piece.
Clearance puzzlesOpenings that start 1.d4 d5. More broadly, positions with locked pawn chains where maneuvering matters more than quick tactics.
Also: coffeehouse chess
A wild, tricky, attack-at-all-costs style, named after the cafés where people played for fun and small stakes.
A forcing series of moves, often starting with a sacrifice, that achieves a clear gain. A combination usually links several tactics together.
Also: comp
What you get in return for material you’ve given up, such as a lead in development, an attack or a better structure.
Two passed pawns on neighboring files. They protect each other as they march and are very hard to stop.
Also: cut off
Using a rook to stop the enemy king from crossing a rank or file. In rook endgames, a king cut off from the pawn often decides the game.
Lesson: Cutting Off the KingA position so equal that neither side has any realistic way to win.
Also: attraction
Luring an enemy piece, often the king, onto a bad square, usually with a sacrifice, so a tactic works there.
Lesson: DecoysForcing a defending piece away from the square or piece it guards, often with a capture or check it has to answer.
Lesson: DeflectionAn older English and Spanish notation where squares are named from each player’s side, as in P-K4 for 1.e4. You will find it in many classic books.
A piece that is lost anyway sells itself as dearly as possible, capturing something on its way out.
Also: develop
Bringing your pieces off the back rank to active squares in the opening. Knights and bishops first, then castle and connect your rooks.
Lesson: Develop Your PiecesA slanting line of squares of the same color. Bishops and queens move along diagonals.
Diagonals are named by their end squares, like the a1–h8 “long diagonal” that a fianchettoed bishop loves.
Moving one piece out of the way to unleash an attack by another piece behind it. The moving piece is free to make a threat of its own.
Lesson: Discovered AttacksA discovered attack where the unleashed piece gives check. The piece that moved can go almost anywhere, often grabbing material for free.
Discovered check puzzlesAny move that creates two threats at once, such as attacking two pieces, or a piece and a mate. A fork is the most common kind.
Two pieces give check at the same time, usually through a discovered check. Blocking or capturing can’t stop both, so the king must move.
Lesson: Discovered & Double CheckTwo pawns of the same color on the same file, after a capture. They can’t protect each other and often become weak.
A game that ends without a winner. Each player usually scores half a point.
Draws happen by stalemate, agreement, threefold repetition, the fifty-move rule, insufficient material, or when a player runs out of time but the opponent has no way to checkmate.
Lesson: Repeat, Count and AgreeAlso: ?!
?! marks a doubtful move: not a clear mistake, but probably not the best either.
Also: ECO
A letter-and-number code from A00 to E99 that classifies openings, from the Encyclopaedia of Chess Openings. For example, the Sicilian Defense is in the B20–B99 range.
Also: Elo, rating
A number estimating playing strength, named after Arpad Elo. Beat a higher-rated player and you gain more points; lose to a lower-rated one and you drop more.
The system predicts an expected score from the rating difference, then nudges your rating toward your actual results. FIDE adopted it in 1970.
Blog: How chess ratings workAlso: e.p., in passing
When a pawn moves two squares and lands beside an enemy pawn, that enemy pawn may capture it as if it had moved only one square. It must be done on the very next move or the chance is gone.
Blog: En passant explainedFrench for “in take”: a piece that can be captured for free. Another way of saying it is hanging.
Also: ending
The final phase of the game, when most pieces have been traded. Kings become fighting pieces and pawns race to promote.
Endgame trainerAlso: chess engine, Stockfish, computer
A computer program that plays and analyzes chess, far stronger than any human. Stockfish is the best-known free engine, and it powers our analysis and review.
Analysis boardA queen mates a king whose two side squares are blocked by its own pieces, like the epaulettes on a uniform’s shoulders.
Epaulette mate puzzlesAlso: eval, evaluation bar
An estimate of who is better and by how much. Engines give it in pawns (+1.5 means White is about a pawn and a half better) or as a forced mate, like #3.
Annotators also use symbols: += (White slightly better), +- (White winning), = (equal) and their mirror images for Black.
Analysis boardAlso: exchange sac
Giving up a rook for a bishop or knight on purpose, for activity, structure or attack.
Lesson: Quiet Moves & Exchange SacsAlso: Forsyth–Edwards Notation
Forsyth–Edwards Notation: one line of text that describes a whole position, including whose move it is, castling rights and the en passant square.
The starting position is rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1.
Tool: Board EditorItalian for “little flank”: developing a bishop to b2 or g2 (b7 or g7 for Black) after moving the knight’s pawn one square, so it controls a long diagonal.
The International Chess Federation, which writes the official rules, runs the world championship and awards titles and ratings.
Also: 50-move rule, 75-move rule
A player can claim a draw if the last fifty moves by each side contained no capture and no pawn move.
Under FIDE rules the game is drawn automatically after seventy-five such moves, even if nobody claims. Online, the draw is usually applied for you.
Lesson: Repeat, Count and AgreeA vertical column of the board. Files are lettered a to h, from White’s left to right.
Lesson: The BoardOld slang for a weak player who is easy to beat, especially in casual games for stakes.
Also: flag fall, flagging, flagged
Running out of time is called flagging, after the little flag on old mechanical clocks. If your flag falls you lose, unless your opponent has no way to checkmate, in which case it is a draw.
The fastest possible checkmate: 1.f3 e5 2.g4 Qh4#. It only happens if White weakens the king with both pawn moves.
Lesson: Fool’s Mate & Légal’s TrapAlso: mate in 2, mate in N, mate in one
A sequence that ends in checkmate whatever the opponent does. “Mate in 3” means checkmate on your third move against any defense.
Mate in 2 puzzlesAlso: double attack, family fork, royal fork
One piece attacks two or more enemy pieces at once. The opponent can usually save only one of them.
Knights are famous for forks because their attacks are hard to see. A knight fork of king and queen is sometimes called a royal fork.
Fork puzzlesA defensive setup the stronger side can’t break through, even with extra material. The game ends in a draw.
Also: French
1.e4 e6 followed by …d5: a solid defense where Black challenges the center and often gets a cramped but sturdy position.
French DefenseAlso: Fried Liver
A sharp line of the Two Knights Defense: 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 d5 5.exd5 Nxd5? 6.Nxf7!, sacrificing a knight to drag Black’s king into the open.
Lesson: The Fried LiverAn opening where one side offers material, usually a pawn, for faster development, the center or an attack.
Lesson: GambitsAlso: Glicko-2, rating deviation
A rating system by Mark Glickman that adds a “rating deviation”: a measure of how sure the system is about your number. New or inactive players move faster.
A bishop whose own pawns are mostly on the other color, so its diagonals are open.
Lesson: Good & Bad BishopsAlso: GM
The highest lifetime title FIDE awards. It requires reaching a 2500 rating and scoring grandmaster “norms” in strong tournaments.
Also: Greek gift sacrifice, Bxh7+
The classic bishop sacrifice on h7 (or h2) against a castled king, usually followed by a knight check on g5 and the queen joining the attack.
It works best when the defending knight has been chased from f6 and the attacker can bring the queen to h5 quickly.
Lesson: The Greek GiftAlso: semi-open file
A file with pawns of only one color on it. The side without a pawn there can use it to put pressure on the enemy pawn.
Two pawns side by side, usually on c4 and d4 or c5 and d5, with no friendly pawns on the files next to them. They control the center but can become targets.
Not to be confused with a hanging piece, which is simply undefended.
Also: hanging, undefended piece, loose piece
A piece that is attacked and not defended enough, so it can simply be captured. Spotting hanging pieces, yours and theirs, is the first skill of tactics.
Lesson: Hanging PiecesA weak square in your own camp, often in front of your pawns, that an enemy piece can occupy permanently.
Lesson: Weak Squares & HolesMaking a move and hoping your opponent doesn’t find the reply that refutes it, instead of checking. The cure is a blunder check before every move.
Lesson: Time & the Blunder CheckA school of thought from the 1920s: control the center from a distance with pieces, often fianchettoed bishops, instead of occupying it with pawns at once.
A move the rules don’t allow, such as leaving your own king in check. Online boards simply refuse them; over the board, the move must be taken back and penalties can apply.
In computer game review, a move that is a little worse than the best one but doesn’t change the result. Milder than a mistake.
Game reviewAlso: Fischer increment, bonus time
Extra time added to your clock after each move you make. It means you can never be completely stuck with zero seconds for a simple move.
The ability to keep making threats so your opponent has to keep reacting. The side with the initiative decides what the game is about.
Also: dead position
When neither side has enough pieces left to deliver checkmate, the game is a draw. King vs king, king and bishop vs king, and king and knight vs king are the classic cases.
Lesson: Not Enough to MateAlso: !?, speculative move
!? marks an interesting or risky move that deserves attention, even if it may not be objectively best.
Placing a piece on a line between an enemy piece and the square it defends, cutting the connection.
Interference puzzlesAlso: IM
The FIDE title one step below grandmaster. It requires a 2400 rating and international master norms.
Also: isolani, IQP, isolated queen’s pawn
A pawn with no friendly pawns on the files next to it, so no pawn can ever defend it.
An isolated d-pawn gives active piece play and open lines, but it can become a target in the endgame.
Lesson: Pawn WeaknessesAlso: Giuoco Piano
1.e4 e5 2.Nf3 Nc6 3.Bc4: White develops quickly and aims the bishop at f7. A classic first opening for beginners.
Italian GameAlso: critical squares
Squares that, if your king reaches them, guarantee the pawn promotes, whatever the defender does.
Endgame: Grab the key squaresHow well protected your king is, usually by castling behind unmoved pawns. A weak king can outweigh a big material advantage.
Lesson: Castle and ConnectAlso: Kings Gambit
1.e4 e5 2.f4: White offers a pawn to open the f-file and grab the center. A favorite of the romantic era.
King’s Gambit AcceptedAlso: KID
A hypermodern defense to 1.d4 where Black fianchettoes the dark-squared bishop, lets White build a big center, then strikes back with …e5 or …c5.
King’s Indian DefenseThe half of the board where the kings start: the e- to h-files. Castling on this side is written O-O.
Also: Legal trap, Légal’s trap
An opening trap where White sacrifices the queen, then mates with the minor pieces. It is named after the 18th-century French player Sire de Légal.
Lesson: Fool’s Mate & Légal’s TrapAlso: London
A setup for White with d4, Bf4, e3, Nf3 and c3 that can be played against almost anything. Popular with club players because the plans stay the same.
London SystemAlso: Lucena, building a bridge
The key winning position in rook and pawn vs rook: the pawn is on the seventh, its king is on the promotion square, and the defending king is cut off. White wins by “building a bridge” with the rook to shelter the king from checks.
Endgame: Lucena positionGerman for “air”: a pawn move in front of the castled king that gives it an escape square and prevents back-rank mates.
The most important and most often played continuation of an opening.
Also: heavy piece
A rook or a queen. Major pieces can force checkmate with just the king’s help.
The pieces and pawns each side has on the board. Being “up material” means having more points’ worth than your opponent.
A position where the enemy king is trapped and checkmate can no longer be avoided, even if it hasn’t happened yet.
A bishop or a knight. Each is worth about three pawns.
Advancing fewer pawns against more on one wing to break up the opponent’s pawns and leave them with a weakness. A typical plan in the Queen’s Gambit Declined Exchange Variation.
Also: ?
A single question mark marks a mistake: a move that noticeably worsens your position.
Game reviewAccidentally dropping a piece on the wrong square online. A favorite excuse, sometimes even true.
Also: TN, theoretical novelty
A move in a known opening position that hasn’t been played before in serious games.
A file with no pawns on it. Rooks love open files because they can travel along them into the enemy position.
Lesson: Open Files & the 7th RankAlso: double king pawn opening, 1.e4 e5
Openings that start 1.e4 e5. More broadly, any position with open lines and few locked pawns.
The first phase of the game, when both sides develop pieces, fight for the center and castle. Named sequences of opening moves are also called openings.
Opening explorerAlso: theory, book
The body of known, analyzed opening moves. “Knowing theory” means remembering the main lines and why they are played.
For improving players, understanding the ideas matters far more than memorizing long lines.
Opening explorerAlso: trap
A sneaky opening line where a natural-looking reply loses quickly. Good to know so you don’t fall for them; not something to build your openings around.
Opening tactics puzzlesAlso: bishops of opposite color
Each side has one bishop and they move on different colors, so they never meet. In pure endgames they are famous for drawing even a pawn or two down; in the middlegame they favor the attacker.
Lesson: Opposite-Colored BishopsAlso: direct opposition, distant opposition
Kings facing each other with one square between them. The side that does NOT have to move “has the opposition”, because the other king must give way.
When the kings stand further apart on the same line with an odd number of squares between them (three or five), it is called distant opposition.
Lesson: The OppositionA square in or near enemy territory where your piece, especially a knight, can’t be chased away by enemy pawns.
Lesson: Knight OutpostsA passed pawn far from the other pawns. It drags the enemy king away so your king can feast on the other side.
Endgame: Outside passed pawnAlso: overloaded piece
One defender has too many jobs. Make it do one, and the other thing it protected falls.
Lesson: Overloading & X-RayDefending a key square or pawn with more pieces than it currently needs, so those pieces are well placed when the fight comes. An idea associated with Aron Nimzowitsch.
Also: passer
A pawn with no enemy pawns in front of it or on the files next to it, so no pawn can stop it on its way to promotion.
Lesson: Passed Pawns & Pawn ChainsAn affectionate (or not so affectionate) word for a weak player, from German. Most strong players call themselves patzers at some point.
A diagonal line of pawns, each protecting the one in front. The usual plan is to attack the base of the opponent’s chain.
Lesson: Passed Pawns & Pawn ChainsA group of pawns separated from your other pawns by empty files. In general, fewer pawn islands is better.
Having more pawns than your opponent on one side of the board. A healthy majority can usually create a passed pawn.
Pushing several pawns toward the enemy king to pry open lines for an attack. Most common when the kings have castled on opposite sides.
Also: pawn skeleton
The arrangement of both sides’ pawns. Because pawns can’t move backward, the structure shapes the plans for the whole game.
Lesson: Pawn WeaknessesAlso: perpetual
A series of checks the opponent can’t escape. The game ends in a draw by repetition, which makes perpetual check a favorite rescue for the losing side.
Also: Portable Game Notation
Portable Game Notation: a plain-text format for saving games, with tags like the players’ names followed by the moves in algebraic notation.
Analysis boardAlso: Philidor defense, third-rank defense
The key drawing method in rook and pawn vs rook: the defender keeps the rook on their third rank to stop the enemy king, then checks from behind once the pawn advances.
Named after François-André Danican Philidor, the great 18th-century player.
Endgame: Philidor positionAlso: point values, material
A rough points system for comparing material: pawn 1, knight 3, bishop 3, rook 5, queen 9. The king is priceless.
They are a guide, not a law. Activity, king safety and pawn structure can make a “3” worth more than a “5”.
Blog: Chess piece valuesAlso: absolute pin, relative pin
A piece can’t move because it would expose a more valuable piece behind it. If that piece is the king, the pin is absolute and moving is illegal.
A relative pin (in front of a queen or rook) can legally be broken, but it usually costs material.
Lesson: PinsA goal for the next several moves, based on the position: attack a weakness, improve your worst piece, or push a pawn majority.
Lesson: Making a PlanAlso: half-move
One move by one player. A full move in notation, like 1.e4 e5, is two plies.
In online chess, entering your next move before your opponent has played theirs, so it happens instantly. Essential in bullet, dangerous if they don’t play what you expected.
Also: two weaknesses
One weakness can usually be defended. Create a second one on the other side of the board, and the defender can’t cover both.
Lesson: The Principle of Two WeaknessesAlso: queening, promote
A pawn that reaches the far rank must be exchanged for a queen, rook, bishop or knight of the same color. Almost always it becomes a queen.
Lesson: PromotionA move that prevents your opponent’s plan before it starts. It begins with asking: what does my opponent want?
Lesson: What Does My Opponent Want?A passed pawn defended by another pawn. The enemy king can’t simply capture it, so it often ties down the defense for the whole endgame.
Also: promotion square
The square on the last rank where a pawn will promote.
Also: QGD, QGA, Queens Gambit
1.d4 d5 2.c4: White offers the c-pawn to pull Black’s d-pawn away from the center. Black can accept (2…dxc4) or decline (2…e6).
Queen’s Gambit DeclinedThe half of the board where the queens start: the a- to d-files. Castling on this side is written O-O-O.
A move in a combination that is not a check, capture or direct threat, but sets up an unstoppable blow. Quiet moves are easy to miss for both players.
Quiet move puzzlesA horizontal row of the board. Ranks are numbered 1 to 8, starting from White’s side.
White’s pieces start on the 1st and 2nd ranks, Black’s on the 7th and 8th. “The seventh rank” always means the one closest to the opponent’s back rank, from the point of view of whoever is talking.
Lesson: The BoardChess with more than ten but under sixty minutes per player. Fast enough for an evening, slow enough to think.
Also: undermining, capturing the defender
Capturing or driving off the piece that protects something, so the thing it protected can be taken.
Lesson: Removing the DefenderThe set of openings you choose to play as White and as Black. A small, consistent repertoire is easier to learn deeply.
Lesson: Your RepertoireAlso: Reti maneuver, Réti study
A king walking diagonally to chase two goals at once: catching an enemy pawn and supporting its own. Richard Réti’s 1921 study is the famous example.
Also: romantic era
The swashbuckling 19th-century style of gambits, sacrifices and direct king attacks, before defense was taken seriously.
Bringing a rook up the board along a rank, for example Re1–e3–h3, to join an attack on the king.
Also: square of the pawn
A shortcut to see whether a king can catch a passed pawn: picture a square from the pawn to its promotion rank. If the king is inside it, or can step in on its move, it catches the pawn.
Lesson: The Rule of the SquareAlso: sac
Deliberately giving up material to get something better: a mating attack, a winning tactic or a lasting positional edge.
Blog: What is a brilliant move?Also: sandbagger
Deliberately losing games to keep a rating low, for example to win lower-rated prize sections. It is against the rules.
Also: four-move checkmate, 4 move checkmate
A quick checkmate where White’s queen and bishop team up on f7: 1.e4 e5 2.Bc4 Nc6 3.Qh5 Nf6?? 4.Qxf7#. Easy to stop once you know it.
Blog: Scholar’s Mate and how to stop itOpenings where White plays 1.e4 and Black answers with anything except 1…e5, like the Sicilian, French or Caro-Kann.
Also: 7th rank, pig on the seventh
For White, the 7th rank; for Black, the 2nd. A rook there attacks pawns that can’t be defended by other pawns and traps the enemy king on its back rank.
Lesson: Open Files & the 7th RankAlso: body check
Using your king to block the enemy king’s path, like a basketball player boxing out, so it can’t reach the important squares in time.
Also: Sicilian
1.e4 c5: Black fights for d4 with a flank pawn and creates an unbalanced game. The most popular reply to 1.e4 at master level.
Sicilian DefenseA less common branch of an opening. Sidelines can be a good surprise weapon or a way to avoid heavy theory.
Also: simultaneous exhibition
A strong player takes on many opponents at once, walking from board to board and making one move at each.
The reverse of a pin: a valuable piece is attacked, and when it moves away, a piece behind it on the same line is captured.
Lesson: SkewersA knight checkmates a king that is completely surrounded, “smothered”, by its own pieces.
Lesson: Smothered MateHow much of the board you control, mostly decided by how far your pawns have advanced. More space gives your pieces room; less space can leave them cramped.
A pointless check given just before resigning or getting mated, purely out of spite.
The player to move is not in check but has no legal move. The game is a draw, which can rescue a player who is far behind.
Lesson: StalemateAlso: positional play
Long-term planning: improving pieces, creating weaknesses and choosing pawn structures. Tactics are what you do when there is something to do; strategy is what you do when there isn’t.
Lesson: Making a PlanEscaping with a draw or win from a lost position through tricks, traps or sheer stubbornness.
Also: rooks behind passed pawns
Rooks belong behind passed pawns, yours or your opponent’s. Behind your own pawn the rook gains scope as the pawn advances; behind theirs it keeps pushing them back.
Lesson: Active RooksAlso: tempi, gain a tempo
A single move considered as a unit of time. You “gain a tempo” when your developing move also forces your opponent to react, for example by attacking their queen.
Also: win the exchange, up the exchange
The difference between a rook and a minor piece. Winning a rook for a bishop or knight is “winning the exchange”.
Not to be confused with “an exchange”, which just means trading pieces of equal value.
What a move intends to do next if it isn’t stopped, such as capturing a piece or mating. Always ask what your opponent’s last move threatens.
Lesson: Checks, Captures, ThreatsAlso: repetition, fivefold repetition
If the same position occurs three times, with the same player to move and the same castling and en passant rights, a draw can be claimed.
The repetitions don’t have to be in a row. Under FIDE rules a fivefold repetition is drawn automatically.
Also: on tilt, tilted
Playing worse after a frustrating loss because you are angry or chasing your rating back. The fix: take a break.
How much thinking time each player gets, such as “5+3”: five minutes each plus three seconds added after every move.
Tool: Chess ClockAlso: touch move rule, j’adoube
In over-the-board play, if you deliberately touch one of your pieces you must move it, and if you touch an opponent’s piece you must capture it, as long as that is legal.
To straighten a piece without having to move it, say “I adjust” (or the French “j’adoube”) first.
Also: exchange, swap
Capturing a piece and letting your opponent capture one of yours back. Trades are good when they help your position, such as when you are ahead in material.
Lesson: Good and Bad TradesReaching the same position through a different move order. Openings transpose into each other all the time.
A piece with no safe squares to run to. Once it is attacked it can’t escape and will be lost.
Trapped piece puzzlesA king maneuver over three squares in a triangle that “loses” a move, handing the obligation to move to the opponent so you win the opposition.
Lesson: TriangulationPromoting a pawn to something other than a queen. It is rare, but sometimes a knight gives a winning check or a rook or bishop avoids stalemate.
Lesson: UnderpromotionA square your pawns can no longer protect, so enemy pieces can settle on it.
Lesson: Weak Squares & HolesAlso: seesaw
A repeating sequence of discovered checks: one piece checks, the king steps aside, and the other piece captures something with discovered check, again and again.
A player who moves the pieces without much of a plan. Also a self-deprecating name for any keen amateur.
Also: wrong rook pawn, wrong-colored bishop
King, bishop and rook pawn can’t win if the bishop doesn’t control the promotion square and the defending king reaches the corner.
Endgame: The wrong bishopAlso: x-ray attack
A piece attacks or defends a square through another piece standing in the way. When the blocker moves or is captured, the x-ray becomes real.
X-ray puzzlesAlso: time trouble, time scramble
German for “time trouble”: having very little time left for the moves you still need to make. Blunders love zeitnot.
Lesson: Time & the Blunder CheckGerman for “compulsion to move”: a position where the player to move would be fine if they could pass, but every legal move makes things worse.
Zugzwang puzzlesAlso: in-between move, intermezzo
German for “in-between move”: instead of making the expected reply, such as recapturing, you first play a stronger forcing move.
Lesson: In-Between MovesEvery idea on this page shows up in our free interactive lessons and puzzles.
