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transonic

American  
[tran-son-ik] / trænˈsɒn ɪk /

adjective

Chiefly Aeronautics.
  1. close to the speed of propagation of sound; moving at 700–780 miles per hour (1127–1255 km/h) at sea level.


transonic British  
/ trænˈsɒnɪk /

adjective

  1. of or relating to conditions when travelling at or near the speed of sound

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

transonic Scientific  
/ trăn-sŏnĭk /
  1. Relating to or capable of speeds at or near the speed of sound (at or approaching Mach 1) or to aerodynamic conditions for bodies travelling at such speeds.

  2. Compare hypersonic subsonic supersonic


Etymology

Origin of transonic

First recorded in 1940–45; trans- + sonic

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

His research lies in the field of viscous gas dynamics, or the study of how gases move around physical objects – like missiles and jets - during transonic and supersonic flights.

From Reuters

“They start wanting to go supersonic, and you don’t want to even let them go transonic because you get much more turbulent effects.”

From The Verge

Hurley said he could feel when the rocket went transonic and broke the sound barrier.

From Seattle Times

Early in the development of the 737 MAX, engineers gathered at Boeing’s transonic wind tunnel in Seattle to test the jet’s aerodynamics using a scale model with a wingspan comparable to that of an eagle.

From Seattle Times

Stucky found no reason for inching into space, and wanted the rocket to burn long enough to get him well beyond the transonic zone.

From The New Yorker