1. The time period during which military and civilian agencies are prepared for an enemy air attack 
2. The condition in which combat aircraft are airborne and ready for an operation
   "aircraft in the Mideast are on air alert" 
3. The warning signal that begins a period of preparation for an enemy air attack

Derived forms: air alerts

Type of: alarm, alarum, alert, period, period of time, qui vive, time period, warning signal

• fly high
• fly honeysuckle
• fly in the face of
• fly in the ointment
• fly in the teeth of
• fly off the handle
• fly on
• fly on the wall
• fly open
• fly orchid
• fly poison
• fly rod
• fly sheet
• fly tent
• fly the coop
• fly tipper
• fly-by
• fly-by-night
• fly-fishing
• fly-half
• fly-tip
• flyaway
• flyblown
• flybridge
• flycatcher