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sonic vs. supersonic

[son-ik] / ˈsɒn ɪk /

adjective

  1. of or relating to sound.

  2. noting or pertaining to a speed equal to that of sound in air at the same height above sea level.

[soo-per-son-ik] / ˌsu pərˈsɒn ɪk /

adjective

  1. greater than the speed of sound waves through air.

  2. capable of achieving such speed.

    a supersonic plane.

  3. ultrasonic.