(or out of a clear blue sky) informal
See parent entry: blue
Without warning; unexpectedly: she phoned me out of the blue
[with reference to a ‘blue’ (i.e. clear) sky, from which nothing unusual is expected]
More example sentences
- Rarely does a profit warning come out of the blue like the subsequent share price reaction suggests.
- Quite frankly, this piece of research is so unexpected, so out of the blue, it beggars belief.
- This particular warning came out of the blue and there must be a worry that there is yet more to come.
Definition of out of the blue in:
- The US English dictionary