# castle

/ˈkæsəɫ/ (US) · /kˈɑːsəl/ (UK)

Source: https://englishreference.com/word/castle
Updated: 2026-08-15

## Senses

### 1. fortified building

noun · CEFR A2

a large building with high, thick walls built long ago to protect people against enemies.

For teachers: a large, fortified residence or compound, typically dating from the medieval period, designed to withstand siege and house nobility.

- The king lived in a stone castle on top of the hill to see enemies coming.
- The medieval castle featured a deep moat and thick curtain walls designed to repel prolonged sieges by rival lords.

### 2. chess piece

noun · CEFR B1 · Informal

a chess piece that looks like a small tower.

For teachers: a common informal name for the rook, a chess piece that moves in straight lines.

- He moved his castle across the board to put the king in danger.
- The beginner mistakenly referred to the rook as a castle throughout the entire tournament match.

### 3. chess move

verb · CEFR B2 · Technical

to move your king and a tower piece at the same time in a special chess move.

For teachers: to execute a special move in chess involving the king and either rook to improve king safety.

- It is usually a good idea to castle early in the game to keep your king safe.
- The grandmaster decided to castle kingside to consolidate his defensive position before launching a counter-attack.

Usage: The verb is usually intransitive and follows specific rules regarding previous moves and check.

## Examples

- The king lived in a stone castle on top of the hill.
- Tourists often visit the medieval castle to see the thick stone walls and the deep ditch surrounding the main gate.
- While many structures from that era have crumbled into ruins, this castle remains perfectly preserved, offering a rare glimpse into the defensive architecture of the fourteenth century.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.