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

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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.

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Example Sentences

Experts warn that the heatwave which gripped the UK this week is not a "one-off" and should act as a "wake-up call" for the country to prepare for a Mediterranean climate.

From BBC • Jun. 28, 2026

"It is a wake-up call for the ANC."

From Barron's • Jun. 25, 2026

Still its successes were a wake-up call for Kyiv that interdiction needed to become a priority, several sources told me.

From The Wall Street Journal • Jun. 24, 2026

State regulators have launched an investigation into the incident, and some local officials have called it a wake-up call for communities like Boyle Heights, where homes are sandwiched close to industry and manufacturing districts.

From Los Angeles Times • Jun. 23, 2026

I basically hung out in my room, listening to tunes and trying to catch some zees after the four A.M. wake-up call.

From "Anthem of a Reluctant Prophet" by Joanne Proulx