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