adj 1  :  ULTRASONIC 1  2  :  of, being, or relating to speeds from one to five times the speed of sound in air - compare SONIC   3  :  moving, capable of moving, or utilizing air currents moving at supersonic speed  4  :  relating to supersonic airplanes or missiles <the age>  su*per*son*i*cal*ly adv 
, n 1  :  a supersonic wave or frequency  2  :  a supersonic airplane .
 
 
 
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