wake-up call

British  

noun

1. a telephone call that wakes a person from sleep

2. an event that alerts people to a danger or difficulty

---

wake-up call Idioms  

1. A portentous event, report, or situation that brings an issue to immediate attention. For example, The rise in unemployment has given a wake-up call to state governments, or The success of the online subscription is a wake-up call to publishers. This metaphoric term originated in the second half of the 1900s for a telephone call arranged in advance to awaken a sleeper, especially in a hotel. Its figurative use dates from about 1990.

---

Example Sentences

I think that was a wake-up call for people in the national security space that there were opportunities for improvement in America’s ability in manufacturing its own solutions.

From The Wall Street Journal

If there are young kids in the house, giddy early wake-up calls are a given.

From BBC

That was a wake-up call to the people of Grand Rapids.

From The Wall Street Journal

Royal Mail managers said Ms Wealleans' death had been a "wake-up call" and apologised for failures to "protect" her.

From BBC

Before that, there were six earthquakes in the 5 a.m. hour, giving many across the region an unpleasant wake-up call.

From Los Angeles Times