Wake up call is an arrangement made for a telephone to ring at a certain time to serve as an alarm clock.(noun)
An example of a wake up call is when you tell the hotel front desk to call you at 7:00 AM.
The definition of a wake up call is something that makes you change your behavior or attitude.(noun)
An example of a wake up call is when you have a heart attack and you realize that life is short and you should spend it with your kids instead of working all day.
See wake-up call in Webster's New World College Dictionary
See wake-up call in American Heritage Dictionary 4
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