The noun alert has 3 senses (no senses from tagged texts)
1. alert, qui vive -- (condition of heightened watchfulness or preparation for action; "bombers were put on alert during the crisis")
2. alert, alerting -- (a warning serves to make you more alert to danger)
3. alarm, alert, warning signal, alarum -- (an automatic signal (usually a sound) warning of danger)
Overview of verb alert
The verb alert has 1 sense (first 1 from tagged texts)
1. (9) alarm, alert -- (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")
Overview of adj alert
The adj alert has 4 senses (first 3 from tagged texts)
1. (7) alert -- (very attentive or observant; "an alert and responsive baby is a joy"; "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")
3. (1) alert, awake -- (not unconscious; especially having become conscious; "the patient is now awake and alert")
4. alert, alive, awake -- ((usually followed by `to') showing acute awareness; mentally perceptive; "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")