alert 1 of 3

noun

Definition of alertnext
1
as in warning
the act or an instance of telling beforehand of danger or risk the white flash of the doe's raised tail, giving the "danger" alert to her fawns

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2
as in watchfulness
the state of being constantly attentive and responsive to signs of opportunity, activity, or danger the doctor told the patient to be on the alert for any signs of infection

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Antonyms & Near Antonyms

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

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Antonyms & Near Antonyms

alert

3 of 3

adjective

ə-ˈlərt How to pronounce alert (audio)
1
as in awake
paying close attention usually for the purpose of anticipating approaching danger or opportunity she needed to stay alert throughout the train ride so as not to miss her stop

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Antonyms & Near Antonyms
2
as in cautious
having or showing a close attentiveness to avoiding danger or trouble warned us to be alert to the presence of pickpockets on the crowded bus

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Antonyms & Near Antonyms
3
as in intelligent
having or showing quickness of mind an alert and well-trained sheep dog who can handle difficult situations

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Antonyms & Near Antonyms
4
as in quick
having or showing the ability to respond without delay or hesitation an alert force of commandos, ready to go on a mission at a moment's notice

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Antonyms & Near Antonyms

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
Market participants remained on alert for moves that could suggest intervention. — Bloomberg, Fortune, 7 Aug. 2026 The sudden closures came as temperatures reached into the nineties in the US capital, with excess humidity prompting a heat alert for the city. — News Desk, Artforum, 7 Aug. 2026
Verb
Dudamel’s fame, moreover, alerted the classical music world around the globe to the rich talent El Sistema has produced. — Mark Swed, Los Angeles Times, 12 Aug. 2026 Officials also reminded residents that outdoor warning sirens could be used to alert people outside to seek shelter. — Lila Hempel-Edgers, Chicago Tribune, 12 Aug. 2026
Adjective
Authorities warned residents to remain alert for possible aftershocks as emergency teams continued assessing damage throughout the affected region. — Antonio María Delgado, Miami Herald, 10 Aug. 2026 Brinks Home warns customers about follow-up scams Brinks Home is warning customers to stay alert for suspicious communications related to the breach. — Kurt Knutsson, FOXNews.com, 10 Aug. 2026 See All Example Sentences for alert
Recent Examples of Synonyms for alert
  1. warning
  2. watchfulness
  3. warn
  4. awake
  5. cautious
  6. intelligent
  7. quick
  8. watch
Noun
  • Some news stations would run a warning for viewers before the ad would air, as well as explain the FCC law requiring its airing.
    — Jeff Wagner, CBS News, 11 Aug. 2026
  • Amazon's Accounting Sets A Shorter Clock Amazon's books offer a warning.
    — Robert J. Szczerba, Forbes.com, 11 Aug. 2026
Definition of warning
Noun
  • For now, the consensus among Wall Street’s economists is less alarm than watchfulness.
    — Nick Lichtenberg, Fortune, 7 Aug. 2026
  • But the book’s ruminative watchfulness is unsuccessfully conjugated in this overly sedate play with music, which has the feel of a song cycle, though sung by the fine cast with gorgeous, lonely sorrow.
    — Brian Seibert, New Yorker, 19 June 2026
Definition of watchfulness
Verb
  • The State Bar of California is warning of unauthorized practice of law after a two-year investigation into a Tustin immigration attorney found he allegedly is not licensed to practice law in the United States.
    — Julie Sharp, CBS News, 14 Aug. 2026
  • As the world burns through its oil stockpiles, the urgency of reopening the strait is becoming more pressing, the International Energy Agency warned Wednesday, even as oil prices have fallen.
    — Mustafa Qadri, CNN Money, 14 Aug. 2026
Definition of warn
Adjective
  • After her 2013 accident, Collett spent a week in a coma and only three days awake in hospital before being transferred to Oaksey House in Oxfordshire, England, the Injured Jockeys Fund’s rehabilitation centre.
    — Gemma Redrup, New York Times, 13 Aug. 2026
  • The number one thing that should keep managers awake at night is worrying about whether they are being told the truth about the reality of the situation.
    — Roger Trapp, Forbes.com, 12 Aug. 2026
Definition of awake
Adjective
  • As the use of AI increases, financial experts say consumers should be cautious about fully trusting these tools.
    — ABC News, ABC News, 7 Aug. 2026
  • The Fed may be more cautious about raising interest rates at a time when the labor market appears less stable.
    — Scott Horsley, NPR, 7 Aug. 2026
Definition of cautious
Adjective
  • Deploying renewables paired with intelligent energy conservation and grid management, individuals, businesses, municipalities, and entire countries are earnestly curbing their CO2 emissions.
    — John Vaillant, Time, 8 Aug. 2026
  • Factories, shipyards and warehouses are becoming intelligent.
    — Ariyan Kabir, Fortune, 8 Aug. 2026
Definition of intelligent
Adjective
  • Staff in the South Stand offices would spend the winter months wearing jackets due to a broken boiler and, according to Bruce, only the players quickest to the dressing-room showers could expect to enjoy hot water after games.
    — Philip Buckingham, New York Times, 14 Aug. 2026
  • This is excellent energy for captions, pitches, texts, brainstorming, flirting, or turning a quick idea into something shareable.
    — Tarot.com, Hartford Courant, 13 Aug. 2026
Definition of quick
Noun
  • On October 12, 2025, armed and masked thieves broke into the museum and made off with cash from the register and at least one watch.
    — Devorah Lauter, ARTnews.com, 7 Aug. 2026
  • Ben Cook, a New York creator who posts about watches on TikTok, uses his Meta smart glasses to listen to music on runs and take hands-free calls.
    — Queenie Wong, Los Angeles Times, 7 Aug. 2026
Definition of watch

Phrases Containing alert

Browse Nearby Words

alehouses
alert
alerted
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Cite this Entry

“Alert.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/alert. Accessed 15 Aug. 2026.

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