Definition of alert in English:



  • 1Quick to notice any unusual and potentially dangerous or difficult circumstances; vigilant.

    ‘an alert police officer discovered a lorry full of explosive’
    ‘schools need to be constantly alert to this problem’
    • ‘He is very alert to matters of procedural fairness.’
    • ‘Firstly Ballyfin's Eoin McEvoy had to be very alert to deny Conroy.’
    • ‘So Pacific Islanders today are very alert to their ocean, and their ownership of that ocean, and their custodianship of that ocean.’
    • ‘The man was completely alert to his surroundings.’
    • ‘One consequence is that consumers are more alert to influences than ever before.’
    • ‘You begin to become more alert to your surroundings.’
    • ‘Though at times they don't seem to be the most aware of animals, sheep are very alert to mood swings, and this time was no exception.’
    • ‘One must also be very alert to the fact that some pilgrims of certain nationalities come in bunches and batches and push their way through.’
    • ‘There are signs that Congress is at least somewhat alert to these dangers.’
    • ‘It has however been equally alert to the fact that a State might present a charge in this way, when in reality it was seeking to impede imports, or in circumstances where there was no commercial exchange at all.’
    • ‘And shortly thereafter, several alert readers noticed something very peculiar.’
    • ‘His poetry continued as it began, very alert to Art as politically acquiescent, complicit or compromised.’
    • ‘At the other end Dermot Byrne almost got clear but Farrell Cuddihy was very alert to clear the danger.’
    • ‘In fact, he was very alert to the activity of the minor pieces.’
    • ‘He did not bother answering me, his eyes were almost closed, but the impression he gave was that he was concentrating intensely and quite alert to what was happening around us.’
    • ‘We were all surely alert to the subliminal messages in the deceptive modesty of his glances.’
    • ‘As you revise, you should be very alert to this point.’
    • ‘"Thanks to the efforts of police and the media, the public is more alert to these practices.’
    • ‘I think they're very guarded and very alert to anything that they think might be untoward or suspicious.’
    • ‘Typically alert to nuances, he was among the first to switch into post-mortem analytic mode.’
    vigilant, wide awake, aware, watchful, attentive, observant, circumspect, wary, chary, heedful, canny
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    1. 1.1Able to think clearly; intellectually active.
      ‘she remained active and alert until well into her eighties’
      • ‘The swelling in his face is nearly gone and he's much more alert and active, which is really encouraging.’
      • ‘Throughout his life he remained very alert and active until very recent times.’
      • ‘On his good days, he is very alert mentally and engages clearly with the issues at hand; on other days he finds it difficult to focus.’
      • ‘Ms L was alert and oriented and able to move both lower extremities at the time of transfer.’
      • ‘Tanner was alert and able to answer questions but was not extremely active.’
      • ‘She was a very active and alert lady and was a founder member of Clonaslee ICA.’
      • ‘In both studies, patients were alert and able to communicate by holding up fingers in response to questions and did not themselves complete the instruments.’
      • ‘‘She is a very bright little girl, very alert,’ she said.’
      • ‘Surviving in a comatose state, his mind is still alert and active.’
      • ‘Advocaat was appropriate raw material for such an alert intellect.’
      • ‘‘He was 93 but he remained mentally very alert until the very end although physically he became very ill,’ added Mr Maltin.’
      • ‘It is the first principle of an alert intellect.’
      • ‘She was quite alert and was able to learn the English language rather quickly.’
      • ‘By this time, the sedating medications usually are significantly dissipated, and the patient is alert and oriented and able to lift his or her own leg.’
      • ‘I realise that I must keep mentally alert to delay the process of degeneration.’
      • ‘Still alert and active, she talked to the Evening Press and recalled how she managed to get the youngsters and all her family on to a ship bound for the USA in 1935.’
      • ‘At physical examination at the time of discharge, she was alert and able to converse and had limited flexion in the lower extremities.’
      • ‘Still active and alert Mary attributes her longevity to plenty of hard work, good genes, a healthy lifestyle and a positive outlook on life in general.’
      • ‘Everyone agreed that Mr Sage was an intelligent, alert man, notwithstanding his years.’
      • ‘Undemonstrative, quick-witted, alert and intelligent: he has it all.’
      quick-witted, sharp, bright, quick, keen, perceptive, wide awake, responsive, agile, acute, astute
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  • 1[mass noun] The state of being watchful for possible danger.

    ‘security forces are on the alert for an upsurge in violence’
    • ‘It's still pretty high, but even if it does, we can be on alert to get out of here as soon as possible.’
    • ‘Dalton sees the handwriting on the wall and wants to put the town on alert for possible evacuation, but the request is refused by his politically conscious superior.’
    • ‘Army reserve units have also been placed on alert for possible call-up.’
    • ‘Hospitals and doctors have been placed on alert to be prepared to quarantine patients suspected of suffering from the early stages of the virus.’
    • ‘And now, as his execution by lethal injection nears, some clinics providing abortions are on alert for possible violence.’
    • ‘France was on alert yesterday for a possible upsurge of violence as the country headed into a long holiday weekend, two weeks after rioting broke out in a run-down suburb of the capital.’
    • ‘But the industry was put on alert about the possible tax rises at a conference this month when a representative from the Revenue said the memoranda would need to be reviewed.’
    • ‘Initially, the company was put on alert for possible participation in an airport security mission.’
    • ‘Police guarded key sites in New York, on alert for possible truck bombs, suicide bombers and chemical and biological attack.’
    • ‘So, it makes sense to be on alert in a cautious, sensible way all throughout the country.’
    • ‘However, as they approached and she saw the ambulance and all the patrol cars, she put her defenses on alert and prepared herself for anything.’
    • ‘No matter how carefully drivers stay on alert against unexpected pedestrians rushing out in front of them, disasters will still occur and there are always casualties.’
    • ‘And Ergon Energy stockpiled materials and put crews on alert yesterday in preparation for possible damage to the electricity network.’
    • ‘This was not the case with security forces, however, who remained on alert against possible terror attacks.’
    • ‘Greater Manchester was put on alert today as firemen prepared for the start of a national strike.’
    • ‘But despite the favorable atmosphere, police remained on alert for possible security threats on the session, the officer said.’
    • ‘The main north-south highway was reopened on Thursday but motorists were urged to remain on alert against possible dangers caused by the continuing heavy rains.’
    • ‘Forestry Minister John Browne has urged forest owners to be prepared and on alert and to help to stamp out fires in plantations.’
    • ‘The President had urged the public to be on alert for possible terrorist actions in September or October.’
    • ‘Medical staff in Scarborough have been put on alert for possible infections after a patient at the resort's hospital died of pneumonia.’
    vigilance, watchfulness, carefulness, attentiveness, guardedness, care, caution, cautiousness, wariness, chariness, alertness, circumspection, prudence, heedfulness, heed, mindfulness
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    1. 1.1[count noun]An announcement or signal warning of danger.
      ‘a bomb alert’
      • ‘Preventive alerts and warnings sometimes issued at the local level were not repeated nationally.’
      • ‘If a flood alert is issued, the Association of British Insurers advises that valuables and furniture are shifted to higher floors.’
      • ‘The all-clear had in fact sounded from an initial alert when the bomb was dropped.’
      • ‘The district administration has sounded an alert.’
      • ‘Science may not yet be able to predict earthquakes with complete accuracy, but an early warning network exists in the Pacific Ocean to issue alerts about the danger of tsunamis.’
      • ‘Meanwhile there are fresh alerts of bomb attacks raised.’
      • ‘There have been alerts warning of bombs being hidden in cameras, cell phones, even stuffed toys.’
      • ‘There has been a continual stream of bomb alerts.’
      • ‘Some of his public alerts sound quite fanciful.’
      • ‘A flood alert was sounded in Kinnaur, Shimla, Kulu and Mandi districts last evening after water started overflowing from the lake, bringing along a lot of silt.’
      • ‘On Tuesday computer security experts issued a worldwide alert of the imminent danger to the Internet from the spread of the worm virus.’
      • ‘When I woke up yesterday morning, my Inbox was flooded with news alerts from Karbala, Iskandariyah and Babil.’
      • ‘A bomb alert was issued at a post office in Germany this week after a package waiting to be delivered began vibrating and emitting a strange noise.’
      • ‘In future, flood alerts will be sent out by text message and mobile phone calls as well as pagers, and the agency's website is also being upgraded so it can better handle sudden surges in the number of ‘hits’ during floods.’
      • ‘‘These floods are an alert,’ said Dr Mike Hulme, reader in climatology in the climate research unit at the University of East Anglia.’
      • ‘Yes, it's frustrating to have alerts sounded and then have nothing happen.’
      • ‘Normally it sounds text-message alerts about 90 times a day.’
      • ‘The Environment Agency is hoping to be able to issue flood alerts for all major watercourses in the future.’
      • ‘There were also bomb alerts in Philadelphia and Washington.’
      • ‘The Environment Agency issued flood alerts for several rivers and part of the A12 was sealed off.’
      warning, caution, notification, notice, exhortation, injunction
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    2. 1.2[count noun]A period of vigilance following a warning of danger.
      ‘traffic was halted during the alert’
      • ‘Civil libertarians say the case poses a landmark test of what people can do or whom they can associate with in the age of terror alerts.’
      • ‘Consideration should be given to suspending the collection of all tolls during ozone alerts’
      • ‘In what I earnestly hope will be a source of lessons learned, a large meteor entered Earth's atmosphere near Jakarta this weekend during a terror alert.’
      • ‘I think if we are going to have these high alerts in the future, I think it is incumbent on the attorney general to give us more information.’
      • ‘This weekend sees terror alerts covering a great part of the world.’
      • ‘What To Do During Hurricane Alerts.’
      • ‘The incident follows a similar alert at a post office earlier this week.’
      • ‘A crowd throw petrol bombs and stones at police and army during a security alert in west Belfast.’
      • ‘The country is on a war alert following terrorist attacks on its Parliament building.’
      • ‘When exercising outdoors during a smog alert, even healthy people may cough or wheeze.’
      • ‘Thousands of holidaymakers who lost luggage following the airport security alert earlier this month are unlikely to be able to claim compensation from their insurers, it emerged last week.’
      • ‘How do we explain what appears to be a night and day difference between the year prior to November 2004 and the year since in terms of terror alerts and scares?’
      • ‘Locals say the series of explosions and alerts over the last decade have shattered their confidence in their company's ability to manage the plant without it presenting a hazard to their lives.’
      • ‘The plan, devised with the help of York Council emergency planning co-ordinator Barry Kelly, aims to speed local response when an alert occurs.’
      • ‘The explosions came amid worldwide terror alerts and four days after a series of bombings killed 34 people.’
      • ‘In a nervous age of orange alerts, who will take the place of Mister Rogers?’
      • ‘At the same time, the government has ordered a general alert, canceling all leave and reinforcing positions.’
      • ‘Physicians are asking people to understand the impact smog can have on their health and to take appropriate measures to stay healthy during smog alerts.’
    3. 1.3[count noun]A signal on an electronic device that prompts the user to do something or attracts their attention.
      ‘a vibrating alert is a discreet alternative to ringtones’
      • ‘In this way, this solution will typically filter the number of alerts from security devices down by a factor of 1000 or more.’
      • ‘With the ability to receive simple text messages, Wall Street traders now get real-time alerts whenever a major deal is carried out in overseas financial markets.’
      • ‘The software will send out an alert when the user reaches his or her threshold and can also automatically free up more space for the user, if desired.’
      • ‘Pop-up ads disguised as Windows system administration alerts annoy users and puzzle security experts.’
      • ‘Capabilities are provided for automating customer service requirements and the system provides alerts to tell users when a problem has occurred, such as an invoice that has not been paid.’
      • ‘It took a little getting used to, but after a while, I realised I was back in Singapore, where it doesn't matter if phones ring or SMS alerts beep loudly on the trains.’
      • ‘Register and sign up for your own personalized ticker, and get special news and even e-mail alerts about stocks that matter to you.’
      • ‘In addition, our company has also introduced SMS alerts for worldwide parcel deliveries.’
      • ‘Local severe weather alerts, delivered to city Web pages and individually to e-mail, cell phones or personal digit assistants.’
      • ‘With the news alerts tool, users type in the news topic they would like to track, and choose whether they would like to receive bulletins once a day or ‘as it happens.’’
      • ‘This software can now, for example, send out a real-time alert to Outlook users when it picks up on an appointment conflict.’
      • ‘It is forecast that in the future mobile phones will be used to send multimedia alerts, with audio and images, and electronic greeting cards.’
      • ‘Today's edition carries a security alert for users of Windows.’
      • ‘There is a hands-free speaker mode and a vibrate alert.’
      • ‘However, it was the features of the new release that stood out: the product will now support foreign keys, stored procedures and database alerts.’
      • ‘These bogus alerts directed users to a maliciously constructed Web site run by Papierniak, instead of the genuine PayPal site.’
      • ‘Whenever the number of deaths rises or falls unexpectedly, the software triggers an alert which prompts a clinical investigation into the possible causes.’
      • ‘Still others offer wedding registry data, sports results and even terror alerts.’
      • ‘And if you want to be alerted when a new user is added to the system, ask for alerts on users.’
      • ‘For example, certain software programs allow users to send e-mail alerts.’
      audible warning, purr, purring, ring, ringing, note, tone, beep, bleep, meep, warble, signal, alarm
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  • Warn (someone) of a danger or problem.

    ‘he alerted people to the dangers of smoking’
    ‘police were alerted after three men drove away without paying’
    • ‘Somehow, she made it out to the poolside without alerting anyone inside the house.’
    • ‘Marriages broke up, alerting women to the disadvantages of being financially dependent.’
    • ‘She let out a soft moan that would only reach Cindy's ears, alerting her of her discomfort.’
    • ‘She had just started relaxing when her laptop gave a small beep, alerting her that she had mail.’
    • ‘He alerted colleagues in a bid to warn drivers heading north on the motorway.’
    • ‘She gave him a pointed look, alerting him that she was aware of his duplicity.’
    • ‘This will help avoid changes being made by someone without alerting other people.’
    • ‘Wenger did the game a service by alerting us to the dangers.’
    • ‘We also implemented a new information campaign in our waiting room aimed at alerting young people to the danger of infection.’
    • ‘The ensuing silence was heavy, alerting him to just how still the room was, how lonely.’
    • ‘To be able to take the money out of her pouch without even alerting her would have taken real skill.’
    • ‘Surely it would make more sense to put up an advert outside a football ground alerting men to the dangers of testicular or prostate cancer?’
    • ‘A neighbour was alerted by the commotion and police and ambulance attended the scene.’
    • ‘I mention this by way of alerting you to the only moment in the book where we feel even mildly uncomfortable.’
    • ‘To hunt a man without alerting the people is like finding a needle in a haystack.’
    • ‘The splash was subtle, but it made a noise that was quite loud, alerting anyone close by.’
    • ‘She said the words as loud as she could without alerting the driver of the van that they were both awake.’
    • ‘Lizzie had seen the glow of the flames when she went upstairs and alerted her parents.’
    • ‘Computers can also cut costs by alerting a physician ordering a test that it has already been done.’
    • ‘A pensioner is lucky to be alive after her dog alerted her to the danger of a fire at her home’
    warn, notify, apprise, caution, put on one's guard, forewarn, put on the qui vive, arouse
    tip off, clue in, put in the picture, put wise
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Late 16th century (originally in military use): from French alerte, from Italian all' erta to the watchtower.