castle

n. chateau, palace; turret, tower

v. put in a castle; make a certain move (in a chess game)

A castle is a defensive structure seen as one of the main symbols of the Middle Ages. The term has a history of scholarly debate surrounding its exact meaning, but it is usually regarded as being distinct from the general terms fort or fortress in that it describes a building which serves as a residence and commands a specific territory.
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Noun
1. a large and stately mansion
(synonym) palace
(hypernym) mansion, mansion house, manse, hall, residence
(hyponym) Buckingham Palace
(part-meronym) great hall
2. a large building formerly occupied by a ruler and fortified against attack
(hypernym) fortification, munition
(hyponym) Balmoral Castle
(part-meronym) keep, donjon, dungeon
3. (chess) the piece that can move any number of unoccupied squares in a direction parallel to the sides of the chessboard
(synonym) rook
(hypernym) chessman, chess piece
(classification) chess, chess game
4. interchanging the positions of the king and a rook
(synonym) castling
(hypernym) chess move
Verb
1. move the king two squares toward a rook and in the same move the rook to the square next past the king
(hypernym) move, go
(derivation) rook
(classification) chess, chess game

(v. i.)
To move the castle to the square next to king, and then the king around the castle to the square next beyond it, for the purpose of covering the king.
  

(n.)
Any strong, imposing, and stately mansion.
  

(n.)
A small tower, as on a ship, or an elephant's back.
  

(n.)
A piece, made to represent a castle, used in the game of chess; a rook.
  

(n.)
A fortified residence, especially that of a prince or nobleman; a fortress.
  

A defensive residence of a lord , distinguished from other fortifications in the dual role as residence and fort. Because castles were symbols of lordship over a region, they were the frequent targets in warfare, since they were easily defended by a relatively few men, tying down a much larger force often for months at a time. Early castles, the 'motte' or 'bailey ' styles, were build generally on a hill, a 'keep ' designed to enhance the tactical value of the hill. Over the centuries, these simple defenses were augmented with various ingenious architectural enhancements that improved both their defensive capabilities and their aesthetic qualities.