Advanced Chess Terms
Advanced chess terms — the subtler ideas that reward serious study, explained in plain language by Chesswick.
- Allumwandlung
- Allumwandlung is a chess problem theme in which, across different lines or solutions, a pawn promotes to each of the four possible pieces: queen, rook, bishop and knight.
- Babson Task
- A Babson Task is a chess problem in which White must reply to each of Black’s four possible pawn promotions by promoting to the same piece to deliver mate.
- Bishop Of The Wrong Color
- A bishop of the wrong color cannot control the promotion square of its passed pawn, typically allowing the defending king to draw a king-and-bishop versus king-and-rook-pawn ending by occupying the promotion corner.
- Centaur
- In fairy chess a centaur is a piece that moves either as a knight or as a non-royal king.
- Dirty Flag
- In chess engine code a dirty flag is a boolean marker that signals cached attack maps or evaluation data must be recomputed after the position changes.
- Excelsior
- Excelsior is a chess problem theme in which a single pawn advances from its starting square through successive moves to promotion, typically enabling a surprising mate.
- Extended Fianchetto
- An extended fianchetto develops a bishop to a3, a6, h3 or h6 to control a long diagonal from farther out on the flank than a standard fianchetto.
- Fairy Pieces
- Fairy pieces are chess units whose movement or capture rules differ from the standard king, queen, rook, bishop, knight, and pawn, used chiefly in variants and problems.
- Grasshopper
- A grasshopper is a fairy chess piece that moves any distance along queen lines but must hop over an intervening piece of either color to land immediately beyond it.
- Lucena Position
- The Lucena position is a winning rook-and-pawn versus rook endgame in which the stronger side builds a bridge with its rook to shield the king from checks and promote the pawn.
- Syzygy
- Syzygy tablebases are endgame databases that store perfect-play results and distances for all positions with up to seven pieces, enabling engines to play flawlessly once few pieces remain.
- Windmill
- A windmill is a repeating tactical sequence in which a piece (typically a rook or queen) alternates discovered checks with its supporter to capture multiple enemy units on successive moves.