- 1Quick to notice any unusual and potentially dangerous or difficult circumstances; vigilant: an alert police officer discovered a truck full of explosives schools need to be constantly alert to this problemMore example sentences
- At the other end Dermot Byrne almost got clear but Farrell Cuddihy was very alert to clear the danger.
- There are signs that Congress is at least somewhat alert to these dangers.
- 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.
- 1.1Able to think clearly; intellectually active: she remained active and alert until well into her eightiesMore example sentences
- Throughout his life he remained very alert and active until very recent times.
- Tanner was alert and able to answer questions but was not extremely active.
- 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.
nounBack to top
- 1The state of being watchful for possible danger: security forces were placed on alertMore example sentences
- 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.
- And now, as his execution by lethal injection nears, some clinics providing abortions are on alert for possible violence.
- 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.
- 1.1An announcement or signal warning of danger: a bomb alert an alert sounded and all the fighters took offMore example sentences
- 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.
- The all-clear had in fact sounded from an initial alert when the bomb was dropped.
- The Environment Agency issued flood alerts for several rivers and part of the A12 was sealed off.
- 1.2A period of vigilance in response to a warning of danger: traffic was halted during the alertMore example sentences
- The country is on a war alert following terrorist attacks on its Parliament building.
- The incident follows a similar alert at a post office earlier this week.
- 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.
verb[with object] Back to top
- Warn (someone) of a danger, threat, or problem, typically with the intention of having it avoided or dealt with: he alerted people to the dangers of smoking police were alerted after three men drove away without payingMore example sentences
- Wenger did the game a service by alerting us to the dangers.
- 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 pensioner is lucky to be alive after her dog alerted her to the danger of a fire at her home
on the alert
- Vigilant and prepared: the security forces must be on the alert for an upsurge in violenceMore example sentences
- The terrorist decides where and when he will strike, while the security forces must constantly be on the alert.
- The committee appeals to everyone to exercise more vigilance and to be on the alert at all times, particularly in the run-up to Christmas.
- To avoid overlooking opportunities, we must forever be on the alert.
- More example sentences
- Both Aaron and Ryan moved carefully and alertly, and Ryan had his sword drawn.
- An original thinker always alertly attuned to contemporary culture, he was admired for his intellectual style and the felicity with which he expressed his ideas in his many books and articles.
- Thankfully, however, the deer do wise up quickly, alertly scanning their surroundings for different sounds or a hint of movement that wasn't there the day before.
late 16th century (originally in military use): from French alerte, from Italian all' erta 'to the watchtower'.