What is the Meaning of the Idiom
OUT OF THE BLUE?
unexpectedly; suddenly and without warning; by surprise
The suggestion of the idiom out of the blue is that something suddenly happens in your life, as though it fell from the sky.
Sometimes, people will say out of the clear blue sky.
1. Normally, he never gives her nice gifts and then last week, out of the blue, he gave her a very expensive necklace. There’s something fishy going on. I think he has another girlfriend.
2. Cris thought they were just friends, and then, out of the blue, Jon told her he loved her!
3. I haven’t heard from my cousin for years, and then, out of the blue, she phoned me yesterday to say that she has been thinking of me a lot lately.
Here is an example of the idiom OUT OF THE BLUE used in an online news article:
…the mainstream media, as well as mainstream medicine, often treat breast cancer as something that strikes out of the blue — giving women no choice but to hope they are not one of the “unlucky” ones to get breast cancer.