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

Chuck Yeager’s 1947 flight that broke the sound barrier occurred at Edwards, as well as the first landings of the Space Shuttle in 1981.

From The Wall Street Journal ● Jun. 15, 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

Boom Supersonic’s XB-1 recently became the first civilian jet to break the sound barrier since the Concorde—a development watched closely by the football league as it considers launching franchises in Europe.

From The Wall Street Journal ● Nov. 21, 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

It wasn’t until the class erupted in applause that the sound barrier was broken.

From "Sir Fig Newton and the Science of Persistence" by Sonja Thomas