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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.

See Examples For:

Sillie posted a second video, the cellphone panning to the ruins against a blue-sky backdrop.

From Los Angeles Times ● Jun. 30, 2026

For hours on a crisp, blue-sky day, kite flyers mingled with sign-wavers, sharing space on the National Mall as they pursued their dueling missions.

From Barron's ● Mar. 28, 2026

At the time Higgs, who has since passed away, said in a statement: "I hope this recognition of fundamental science will help raise awareness of the value of blue-sky research."

From BBC ● Mar. 17, 2026

Strauss, a financier in the 1920s of the city’s skyline, summed up the blue-sky optimism: “New York cannot be held back in her growth and development as the supreme city in the world.”

From The Wall Street Journal ● Nov. 8, 2025

I reach for a blue-sky pencil, but pick up midnight black instead.

From "Rules" by Cynthia Lord

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