castle in the air

noun

1. a fanciful or impractical notion or hope; daydream.

castle in the air

noun

1. a hope or desire unlikely to be realized; daydream

Word History and Origins

Origin of castle in the air¹

First recorded in 1570–80

Example Sentences

Often while the lamp burnt low, and a horse-bell jangled sadly, they laughed together in a castle-in-the-air.

From Project Gutenberg