sound barrier

American  

noun

1. Also called transonic barrier.  Also called sonic barrier.  (not in technical use) a hypothetical barrier to flight beyond the speed of sound, so postulated because aircraft undergo an abruptly increasing drag force induced by compression of the surrounding air when traveling near the speed of sound.

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idioms

1. break the sound barrier, to travel faster than the speed of sound.

sound barrier British  

noun

1. Also called: sonic barrier.   transonic barrier.  (not in technical usage) a hypothetical barrier to flight at or above the speed of sound, when a sudden large increase in drag occurs

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Etymology

Origin of sound barrier

First recorded in 1950–55

Example Sentences

See Examples For:

sound barrier

"Even during our religious holidays, even on Good Friday, jets fly over us and break the sound barrier just to scare us," al-Jamal said.

From Barron's ● Apr. 5, 2026

In 1947, with its X-1 plane, the team became the first in the history of human flight to break the sound barrier.

From Los Angeles Times ● Mar. 31, 2026

Chief Executive Bryon Hargis said it isn’t the straightforward engineering of quintupling the sound barrier that has held the U.S. back, but the manufacturing challenge of mass-producing weapons that can do so reliably and economically.

From The Wall Street Journal ● Dec. 5, 2025

Intense sonic booms could be heard overhead as Israeli jets broke the sound barrier.

From BBC ● Oct. 13, 2024

She’d won the 1938 Bendix Air Race flying a fighter plane from Los Angeles to Cleveland, and later in life she would become the first woman to break the sound barrier.

From "A Thousand Sisters" by Elizabeth Wein