[1] : The Collaborative International Dictionary of English v.0.48

supersonic \su`person"ic\, a.
   1. moving at a speed greater than the speed of sound in air;
      -- this speed varies with altitude, since the speed of
      sound varies with altitude, as well as with temperature
      and humidity, being approximately 1129 feet per second at
      sea level and 984 feet per second at 16 miles altitude.
      pjc

   2. capable of moving at speeds higher than the speed of
      sound; -- of aircraft.
      pjc

[2] : WordNet (r) 2.0

supersonic
     adj 1: of speed greater than the speed of sound in a given medium
            especially air; "a supersonic bomber flies so fast
            that it must release its bombs while the target is
            still over the horizon" ant: sonic, subsonic
     2: having frequencies above those of audible sound syn: ultrasonic
see also:
sonic subsonic ultrasonic 

Supersonic >> S Words
Supersonic, definition of term: Supersonic
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