- air alert - the time period during which military and civilian agencies are prepared for an enemy air attack
--1 is a kind of time period, period of time, period
- air alert - the condition in which combat aircraft are airborne and ready for an operation; "aircraft in the Mideast are on air alert"
--2 is a kind of alert, qui vive
- air alert - the warning signal that begins an period of preparation for an enemy air attack
--3 is a kind of alarm, alert, warning signal, alarum
- air alert - the condition in which combat aircraft are airborne and ready for an operation; "aircraft in the Mideast are on air alert"