hypersonic

  1. Adjective.  (context, of a speed) equal to, or greater than, or capable of achieving, five times the speed of sound.
  2. Adjective.  (context, of a speed) far enough above the speed of sound so as to cause significant differences in behaviour due to chemical reactions or disassociation of the air.

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This entry was last updated on RefTopia from its source on 3/20/2012.