Definition of out of a or the clear blue sky in English:

out of a (or the) clear blue sky

  • As a complete surprise: his moods blew up suddenly out of a clear blue sky
    More example sentences
    • Aware that such social tornadoes can twist towards them out of a clear sky, governments have learned to be cautious.
    • When angered, people burn, things break and fly around, lightning may strike out of a clear sky.
    • I've heard of lightning coming out of a clear sky.
See parent entry: clear

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Word of the day maelstrom
Pronunciation: ˈmālˌsträm
noun
a powerful whirlpool in the sea