Castling
/ˈkæsəlɪŋ/A special move in which the king moves two squares toward a rook, which then jumps to the square the king crossed.
Castling is legal only if neither piece has moved before, no pieces stand between them, and the king is not in, does not cross through, and does not land on an attacked square. It is the only move that relocates two pieces at once, and its resemblance to fortifying a stronghold gives the move its name.
Etymology
Castling descends from an earlier, cruder rule called the "king's leap," added to European chess sometime between the 14th and 15th centuries, when a king on its first move could jump two squares in any direction, including like a knight, to reach safety more quickly in the increasingly dynamic modern game. Players began combining this leap with repositioning a rook near the king — first as two separate moves, moving the rook to the f-file and then having the king leap over it to the g-file — and by the 17th century these had merged into the single, simultaneous move known today. Its English name reflects the rook's popular nickname, "the castle": since most other European languages call the rook "tower" (French tour, Italian torre, German Turm), their words for castling — such as roque, arrocco, or rochade — trace to the same tower/fortress root, while English's "castling" and the older habit of calling it "castling the rook" preserve the direct connection to the piece's fortress-shaped identity.
Translations
| Language | Term | Notes |
|---|---|---|
| Arabic | التبييت (at-tabyit) | Lower-confidence entry; Arabic chess terminology for castling varies by region and should be spot-checked. |
| Dutch | rokade | |
| French | roque | Related to the same "tower/rook" root as most European rook names. |
| German | Rochade | Borrowed from French roque with a German noun ending. |
| Italian | arrocco | |
| Polish | roszada | |
| Portuguese | roque | |
| Russian | рокировка (rokirovka) | Adapted from the same French roque root. |
| Spanish | enroque | |
| Turkish | rok loanword | Direct loanword from French/Italian roque/rocco. |