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Use the word "alert" to describe situations in which a person is thinking clearly or is fully awake. There's an awareness of what's happening:

  • Alicia feels alert after a few cups of coffee in the morning.
  • Ted doesn't feel very alert today. He's tired.
  • Alert customers know when things go on sale.
  • Are you alert right now? Are you paying attention?

"Alert" is also a noun. In this case, it's similar to the noun "alarm."

  • The police are on the alert for someone who has been breaking into houses in this area.
  • An alert was sent to parents telling them that the school was on lock down.
  • When the sky turned black, I turned on the TV to see if there was an alert for a tornado.
  • I need your attention! There's an alert.

As a verb, "alert" is similar to "tell" or "inform."

  • We noticed something unusual about a passenger on the train and alerted the conductor.
  • You should alert the police if you see suspicious activity in your neighborhood.


gazelle A gazelle must be alert for hungry predators at all times.



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This page was first published on May 9, 2012. It was updated on February 1, 2016.




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