alert 1 of 3

Definition of alertnext

alert

2 of 3

verb

as in to warn
to give notice to beforehand especially of danger or risk alerted us to the possibility that the roads would be flooded and we might have to take a detour

Synonyms & Similar Words

Antonyms & Near Antonyms

alert

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adjective

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as in intelligent
having or showing quickness of mind an alert and well-trained sheep dog who can handle difficult situations

Synonyms & Similar Words

Antonyms & Near Antonyms

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Synonym Chooser

How does the adjective alert contrast with its synonyms?

Some common synonyms of alert are vigilant, watchful, and wide-awake. While all these words mean "being on the lookout especially for danger or opportunity," alert stresses readiness or promptness in meeting danger or in seizing opportunity.

alert traders anticipated the stock market's slide

When can vigilant be used instead of alert?

The synonyms vigilant and alert are sometimes interchangeable, but vigilant suggests intense, unremitting, wary watchfulness.

eternally vigilant in the safeguarding of democracy

When might watchful be a better fit than alert?

In some situations, the words watchful and alert are roughly equivalent. However, watchful is the least explicit term.

the watchful eye of the department supervisor

When could wide-awake be used to replace alert?

The words wide-awake and alert can be used in similar contexts, but wide-awake applies to watchfulness for opportunities and developments more often than dangers.

wide-awake companies latched onto the new technology

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of alert
Noun
Jim waits 45 minutes after sending a trade alert before buying or selling a stock in his charitable trust’s portfolio. Natasha Abellard, CNBC, 7 Nov. 2025 After the alert went out that a suspect in a double homicide was in the area, an officer spotted the vehicle and attempted a traffic stop. Robb Murray, Twin Cities, 7 Nov. 2025
Verb
They had been alerted that Running Fence was planning to enter the ocean despite having no permit. Literary Hub, 7 Nov. 2025 Shockley and Maycock alerted the ship’s crew but alleged the staff did not take steps to remediate the issue in and around their cabin, according to the complaint. Nathan Diller, USA Today, 7 Nov. 2025
Adjective
Using caffeine regularly builds a tolerance, so more caffeine is needed to feel awake and alert. Ashley Olivine, Verywell Health, 5 Jan. 2026 Braintree Police issued a Be On the Lookout — or BOLO — alert. Flint McColgan, Boston Herald, 4 Jan. 2026 See All Example Sentences for alert
Recent Examples of Synonyms for alert
Noun
  • The impact of the storm was worsened by clogged waterways in an already flood-prone area, and an apparent lack of understanding of early warnings, Bernardo Rafaelito Alejandro IV, deputy administrator for the Philippines Office of Civil Defense told local media.
    Helen Regan, CNN Money, 6 Nov. 2025
  • Strong winds are occurring but are not so strong as to warrant a High wind warning.
    CA Weather Bot, Sacbee.com, 6 Nov. 2025
Noun
  • This patience is watchfulness, not idleness.
    Francois Botha, Forbes.com, 7 Sep. 2025
Verb
  • Israel opened and closed Gaza’s borders with Egypt arbitrarily and without warning.
    Literary Hub, Literary Hub, 10 Nov. 2025
  • The United States and France first warned more than a decade ago that Russian satellites appeared to be spying and collecting information on their assets, including on commercially run satellites.
    Lauren Kent, CNN Money, 9 Nov. 2025
Adjective
  • All the firefighters were awake and alert, Esposito said.
    Phil Helsel, NBC news, 6 Nov. 2025
  • That night, after the talent show and dinner and homework, Emily lay awake in bed, unable to sleep.
    Jamie Thompson, The Atlantic, 6 Nov. 2025
Adjective
  • Be especially cautious in school zones and watch for children and the flashing lights of school buses.
    NC Weather Bot, Charlotte Observer, 7 Jan. 2026
  • Two years as a mental health patient had taught Virginia to be cautious.
    Literary Hub, Literary Hub, 7 Jan. 2026
Adjective
  • Caterpillar’s intelligent product lineup spans core construction and earthmoving equipment, along with connected site systems.
    Aamir Khollam, Interesting Engineering, 7 Jan. 2026
  • Conversely, if these foundations can be reinforced, even partially, the intelligent age may yet fulfil its promise of progress.
    Klaus Schwab, Time, 5 Jan. 2026
Adjective
  • Green was quick to point out that every team that has won a championship featured a strong defense.
    Jordy Fee-Platt, New York Times, 5 Nov. 2025
  • Take this quick quiz to see where your digital habits stand.
    Kurt Knutsson, FOXNews.com, 5 Nov. 2025
Noun
  • If there is a potential for temperatures to fall into these thresholds, a freeze watch may be issued a few days ahead of time.
    NC Weather Bot, Charlotte Observer, 10 Nov. 2025
  • Sotheby’s estimated nearly a third of its watch sales in 2023 went to buyers age 30 and under, giving them priceless social currency.
    Eva Roytburg, Fortune, 9 Nov. 2025

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Cite this Entry

“Alert.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/alert. Accessed 9 Jan. 2026.

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