castle

The Simple English Wikipedia has an article on:

Castle

Pronunciation

• enPR: käs'(ə)l, IPA ^(key): /ˈkɑːs(ə)l/
• SAMPA: /"kA:s(@)l/

• Audio (US)

  (file)

Noun

Singular castle

Plural castles

1. (countable) A castle is a large, strong building used to protect the people inside.

   In the Middle Ages, castles were used to protect the king and queen.

2. (countable) In chess, the castle is another name for the rook.

• 
  A castle on a hill
• 
  A Japanese castle
• 
  A castle in chess

Verb

Plain form castle

Third-person singular castles

Past tense castled

Past participle castled

Present participle castling

1. (intransitive) In chess, to castle is to take a turn that involves both the rook and the king moving at once.

   I was going to win if he hadn't decided to castle.