phrase🎓 English idiom

out of the blue

unexpectedly

What it means

Happening suddenly and unexpectedly, without any warning or obvious cause. It is used for events, news, or arrivals that take people completely by surprise.

Examples

  • Out of the blue, my old roommate called after ten years of silence.
  • The resignation came out of the blue and shocked the whole office.
  • She got a job offer out of the blue from a company she'd never contacted.
  • His proposal was completely out of the blue; we'd only just met.

Where it comes from

The phrase is a shortening of 'a bolt out of the blue', referring to a lightning strike from a clear blue sky. It became common in the 19th century to describe sudden, surprising events.

Related idioms

#speak of the devil#at the drop of a hat#once in a blue moon#up in the air

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