Definition of alert
(Entry 1 of 3)
alert
nounDefinition of alert (Entry 2 of 3)
1
: a state of careful watching and readiness especially for danger or opportunity
on 24-hour alert
2a
: an alarm or other signal of danger
traffic alerts They sounded the alert.
b
: an urgent notice
… an alert to parents … about new immunization requirements.— Ann Schrader
3
: the period during which an alert is in effect
on the alert
: looking for or expecting something (such as danger or an opportunity)
Drivers need to be on the alert for icy condition. always on the alert for a good bargain
alert
verb
alerted; alerting; alerts
Definition of alert (Entry 3 of 3)
1
: to call (someone) to a state of readiness : warn
alerted the school board of a possible teachers' strike alert the authorities
2
: to make (someone) aware of something
alerted the public to the dangers of pesticides
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Merriam-Webster unabridged
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Time Traveler for alert
The first known use of alert was in 1618
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