castle in the air

noun phrase

variants or less commonly castle in Spain
: an impracticable project : daydream

Examples of castle in the air in a Sentence

Recent Examples on the Web Diamond has spent decades building castles in the air, works rooted in genuine curiosity and an ever-inquisitive spirit. Angelica Aboulhosn, Smithsonian Magazine, 8 Sep. 2023 In doing so, Xi is not constructing theoretical castles in the air to rationalize decisions that the CCP has made for other, more practical reasons. Kevin Rudd, Foreign Affairs, 10 Oct. 2022 The movie keeps flashing, onscreen, how much debt Bogart gets himself into, launching his company like a castle in the air. Owen Gleiberman, Variety, 2 Apr. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'castle in the air.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1566, in the meaning defined above

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

Dictionary Entries Near castle in the air

Cite this Entry

“Castle in the air.” Dictionary, Merriam-Webster, Accessed 2 Mar. 2024.

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