castle in the air

noun phrase

Definition of castle in the air 

: an impracticable project : daydream

called also castle in Spain

First Known Use of castle in the air

1566, in the meaning defined above

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The first known use of castle in the air was in 1566

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What made you want to look up castle in the air? Please tell us where you read or heard it (including the quote, if possible).


obstinately defiant of authority

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