out of the blue

/ˌaʊt əv ðə ˈbluː/INFORMAL · C1

Meaning

completely unexpectedly

Examples

1My old school friend rang me out of the blue after ten years.
2Out of the blue, our new neighbours invited us to their daughter's wedding.
3We hadn't heard from Aunt Rosa in years, and then, out of the blue, she turned up at our door.
4Nobody saw it coming when, out of the blue, the manager announced she was leaving.
5Did the job offer really come out of the blue, or had you applied for it?

Grammar

The phrase does not change. It works like an adverb: at the start or end of a clause, or after a verb such as come, ring or arrive.

Similar in meaning

a bolt from the blue

More idioms about colours

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once in a blue moonvery rarely a white liea small untruth told to avoid hurting someone green with envyvery jealous of what someone else has see redto suddenly become very angry with flying coloursvery successfully, especially in a test a grey areaa situation where the rules are not clear

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