a large and stately mansion

[ Syn: palace ]

a large building formerly occupied by a ruler and fortified against attack

(chess) the piece that can move any number of unoccupied squares in a direction parallel to the sides of the chessboard

[ Syn: rook ]

interchanging the positions of the king and a rook

[ Syn: castling ]

move the king two squares toward a rook and in the same move the rook to the square next past the king