castle
noun
a large and stately mansion
Synonymspalacea 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
Synonymsrookinterchanging the positions of the king and a rook
Synonymscastling
verb
move the king two squares toward a rook and in the same move the rook to the square next past the king
Source: WordNet 3.1, Princeton University
