an automatic signal (usually a sound) warning of danger
a warning serves to make you more alert to danger
condition of heightened watchfulness or preparation for action; "bombers were put on alert during the crisis"
engaged in or accustomed to close observation; "caught by a couple of alert cops"; "alert enough to spot the opportunity when it came"; "constantly alert and vigilant, like a sentinel on duty"
mentally perceptive and responsive;"an alert mind"; "alert to the problems"; "alive to what is going on"; "awake to the dangers of her situation"; "was now awake to the reality of his predicament"
quick and energetic;
warn or arouse to a sense of danger or call to a state of preparedness; "The empty house alarmed him"; "We alerted the new neighbors to the high rate of burglaries"
(sometimes followed by `of') having or showing knowledge or understanding or realization or perception; "was aware of his opponent's hostility"; "became aware of her surroundings"; "aware that he had exceeded the speed limit"
bearing in mind; attentive to; "ever mindful of her health"; "mindful of his responsibilities"; "mindful of these criticisms, I shall attempt to justify my action"