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Synonyms

blue-sky

American  
[bloo-skahy] / ˈbluˈskaɪ /

adjective

  1. fanciful; impractical.

    blue-sky ideas.

  2. (especially of securities) having dubious value; not financially sound.

    a blue-sky stock.


blue-sky British  

noun

  1. (modifier) of or denoting theoretical research without regard to any future application of its result

    a blue-sky project

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. to theorize (about something that may not lead to any practical application)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of blue-sky

First recorded in 1890–95

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“Like, all I think is blue and green. I think of an aerial view of a park. And some grass and a blue sky at prime 11 a.m. sunshine.”

From Los Angeles Times • May 19, 2026

There were all these trouble zones - a bit of blue sky and a big patch of grass - and nobody could get them.

From BBC • Dec. 19, 2025

Near the top of this bleak scene, there’s a peek at the lifting mist and emerging blue sky.

From The Wall Street Journal • Dec. 11, 2025

Under a clear blue sky in the Austrian Alps, the 25-year-old, who started fifth, was able to best navigate the less-than-ideal conditions after recent snow.

From Barron's • Nov. 22, 2025

The massive hologram on the ceiling looks just like a cloudless blue sky.

From "Amari and the Night Brothers" by B.B. Alston

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