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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Time Traveler for castle in the air

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

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Rhyming Dictionary: Words that rhyme with castle in the air

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a tendency to relapse

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