2. The ability to think quickly and intelligently; alert: "Even though Ingrid was a centenarian, she still had an agile mind."
2. An airborne radar that uses a phased-array antenna which changes radar-beam forms and beam positions at electronic speeds.
When combined with digital processing of the radar returns, it can simultaneously provide such functions as beacon-locating, forward-looking mapping, navigation updating, terrain avoidance, and terrain-following in manned strategic bombers and other aircraft.