Definition of "sonic barrier" []

• The sudden sharp increase in aerodynamic drag experienced by aircraft approaching the speed of sound. Also called sound barrier. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "I, on the other hand, am willing to risk going outside the sonic barrier to get those bioscans."