- fanciful; impractical: blue-sky ideas.
- (especially of securities) having dubious value; not financially sound: a blue-sky stock.
Origin of blue-sky
First recorded in 1890–95
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for blue-sky
The beauty of the blue-sky day ignored what had occurred 24 hours before.The Resilient City: New York After 9/11
September 11, 2014
Turn a perfectly sound, entrenched business into a blue-sky factory?The Big Tomorrow
Snubbed for the first time in all her blue-sky life–and by a boy, too!Pemrose Lorry, Camp Fire Girl
Isabel Katherine Hornibrook
The bluest skies of a blue-sky land curved in fathomless majesty over the yellow valley of the Santa Fé.Vanguards of the Plains
There are some business men who look upon psychology as "blue-sky" theorizing or "new thought."Initiative Psychic Energy
The blue-sky during all these centuries has tinged the shadows outdoors a bluish color.Visual Illusions
- (modifier) of or denoting theoretical research without regard to any future application of its resulta blue-sky project
- to theorize (about something that may not lead to any practical application)