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

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

But its treatment in general showed "there are still areas where the #MeToo movement has not yet breached the sound barrier, chiefly in men's football," she added.

From Barron's • Feb. 24, 2026

The test flight of a plane called XB-1, developed by the company Boom Supersonic, became the first civilian jet to break the sound barrier since the Concorde.

From The Wall Street Journal • Nov. 19, 2025

Along the coast in the city of Tyre, Israeli jets are swooping low, breaking the sound barrier - but the beach below is more crowded.

From BBC • Aug. 26, 2024

At NASA’s High-Speed Flight Research Center on Edwards Air Force Base—the place where pilot Chuck Yeager first cracked through the sound barrier in 1947— engineer John Perry manned an X-15 simulator.

From "Hidden Figures" by Margot Lee Shetterly