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.

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blue-sky British  

noun

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

   a blue-sky project

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verb

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

Etymology

Origin of blue-sky

First recorded in 1890–95

Example Sentences

“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

Powerful explosions rocked Tehran for the fourth day running on Tuesday, sending thick clouds of grey smoke into the blue sky, AFP journalists said.

From Barron's • Mar. 3, 2026

Surrounding areas in north-east Scotland might well have seen a little blue sky on Thursday too, but Friday is the day when the cycle will be properly broken and the sunshine will return more widely.

From BBC • Feb. 12, 2026

Once fully committed, the cold is comfortable, and the blue sky helps.

From Salon • Nov. 8, 2025

She looks up, peering as though she is searching for the stars hidden behind the blue sky dotted with fluffy white clouds.

From "The Night Circus" by Erin Morgenstern

Related Words

• absurd
• bizarre
• extravagant
• fantastic
• fantastical
• fictional
• imaginative
• offbeat
• preposterous
• unreal
• whimsical