Definition of castle in English:



  • 1A large building or group of buildings fortified against attack with thick walls, battlements, towers, and in many cases a moat.

    • ‘THE 5ft-thick walls of a medieval castle have seen the light of day again after centuries buried underground.’
    • ‘Defensive walls and ditches were found from the medieval castle, as well as arch and window mouldings and numerous rubbish pits full of food remains and pottery.’
    • ‘In medieval tower houses and castles, the gentry and their servants often slept in the same room, separated only by curtains.’
    • ‘He had heard tales of labyrinthine passages built into the walls of noble castles, and knew that the Princess must know a secret control to open his room into such a passage.’
    • ‘At the heart of the inner ward was a large mound, which this year's dig has revealed covers the remains of a tower house - the castle's main building.’
    • ‘Some time ago, in a country that does not really exist anymore, a man once stood upon the battlements of a castle and surveyed his handiwork.’
    • ‘Equally important is establishing the supply lines of wood and stone essential for more sophisticated buildings and stronger castle fortifications.’
    • ‘Maura was sitting at his desk, reading from a book that was thicker than a wall of the castle.’
    • ‘One of the most familiar forms of fortification, the castle still symbolizes the entire medieval world and seems to define its military outlook.’
    • ‘If they attacked the castle, she would most likely die in the battle.’
    • ‘Later, he began building model castles, surrounded by fortified emplacements, and he spent hours studying the virtually impregnable fortifications of Vauban.’
    • ‘Founded by William the Conqueror, the fine motte and bailey castle was popular with medieval monarchs, some of whom used it as a royal hunting lodge.’
    • ‘Some very strongly fortified castles of this class have an additional wall set a short distance out from the main enceinte and concentric with it, the area between the two walls being termed the outer ward.’
    • ‘The castle has six towers and some twenty distinct roof forms.’
    • ‘You will encounter large mountains, a factory complex, and the large ruins of a medieval castle.’
    • ‘In the heart of the state - the lands around Sofia and in Macedonia - fortified castles were erected to repel Byzantine attacks.’
    • ‘Here, you can see stone cannon balls built into the castle walls, defensive battlements and interior living quarters.’
    • ‘They were inside what was left of the walls of the castle, but the tower was some way distant.’
    • ‘Medieval castles were also designed to be as inaccessible as possible, so look for angles that reveal the inhospitable surroundings and the drama of their location.’
    • ‘I sat in the guard barracks in the outer wall of the castle battlements.’
    fortress, fort, stronghold, fortification, keep, citadel, fastness, tower, peel, palace, chateau, donjon
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    1. 1.1A magnificent and imposing mansion, especially one that is the home or former home of a member of the nobility.
      [in names] ‘Castle Howard’
      • ‘Castle Howard is the property of the Howard family, while Harewood House and Burton Constable belong to trusts.’
      • ‘The real Grace Nugent been a near neighbor, living at Castle Nugent four miles north of Edgeworthstown.’
      • ‘Hopefully soon they would catch up to Ian's caravan, and would return to castle Laramont with Rana.’
      mansion, stately home, hall, manor, big house, manor house, country house, palace
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    2. 1.2Chess informal
      old-fashioned term for rook


  • 1 Make a special move (no more than once in a game by each player) in which the king is transferred from its original square two squares along the back rank toward the corner square of a rook, which is then transferred to the square passed over by the king.

    • ‘And White lost more than a tempo, more like two or three since it took five bishop and knight moves to make the captures and Black did not lose a tempo with castling and only made two capturing moves with his rook and king.’
    • ‘Also, he would like to clear the back rank before he castles to give his Rooks greater maneuverability.’
    • ‘At this point I think Black could simply castle when once again I see nothing wrong with his position.’
    • ‘There isn't anything happening on the kingside for either side. White hasn't castled, which means that his King is in the center.’
    • ‘First off, White can't use this imbalance before Black castles and begins to activate the Bishop, and White can't prevent Black from castling.’
    1. 1.1[with object]Move (the king) by castling.
      • ‘But if the kings are castled on opposite sides and the half-open file bears down on the enemy king, it's a big plus and can easily offset even doubled isolated pawns.’
      • ‘This is a fight he CAN'T win since his King isn't castled and White has more pieces in play than Black does.’
      • ‘‘He's just a crybaby if you ask me,’ the other spat as he castled his king.’
      • ‘He is also ahead in development, and his King is safely castled.’
      • ‘If White's King was castled, then 4.Nxd6 would be equal.’


  • castles in the air (or in spain)

    • Visionary unattainable schemes; daydreams.

      ‘my father built castles in the air about owning a boat’
      • ‘The neurotic is the type of person who's continuously building dream castles in the air.’
      • ‘if you have built castles in the air, your work need not be lost; that is where they should be. now put the foundations under them.’
      • ‘It will be nothing but building castles in the air.’
      • ‘When you're building castles in the air there's little to recommend too much in the way of caution on their location, architecture or facilities.’
      • ‘With investment in public construction projects being so vague, Li stressed that many big construction investments at the time were castles in the air.’
      • ‘Academics aren't the only people to build castles in the air, in fact the almost hypnotic nature of the internet makes it very conducive to castle-making.’
      • ‘Please tell him just to gently post the mail into the box I have so willingly provided, and then tell him to be on his way, to beat his path away from my dreamy semi-consciousness, and leave me to my somnolence, my reverie of castles in the air.’
      • ‘In an interview with the on-line magazine of the newspaper, he said, ‘Instead of constructing castles in the air, we have to support harsh cuts.’’
      • ‘Others would listen spellbound, and describe Heidegger at length building elaborate conceptual castles in the air, only to tear them down a moment later.’
      • ‘Maybe the economy would be growing so fast the voters wouldn't even notice the collapse of all those tall castles in the air.’
      ambition, aspiration, hope
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Late Old English: from Anglo-Norman French and Old Northern French castel, from Latin castellum, diminutive of castrum fort.