air brake

American  

noun

1. a brake or system of brakes operated by compressed air.

2. Aeronautics. a device for reducing the air speed of an aircraft by increasing its drag.

3. a device for stopping the sails of a windmill by disrupting the flow of air around them.

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air brake British  

noun

1. a brake operated by compressed air, esp in heavy vehicles and trains

2. Also called: dive brake.  an articulated flap or small parachute for reducing the speed of an aircraft

3. a rotary fan or propeller connected to a shaft to reduce its speed

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Etymology

Origin of air brake

An Americanism dating back to 1870–75

Example Sentences

The air brake, invented by George Westinghouse in 1869, sent compressed air through a line to enable the train’s engineer to apply brakes from the locomotive.

From Textbooks • Dec. 14, 2022

Union Pacific failed to maintain the rail cars in accordance with federal regulations such as regularly performing single rail car air brake tests, according to the NTSB.

From Washington Times • Jan. 25, 2021

But trucks generally abide by a three-second rule, in part because their air brake systems take a little longer to engage.

From Slate • Jun. 8, 2015

In 1869, when only 23 years old, Westinghouse patented his air brake for stopping trains � now standard equipment for railways all over the world.

From Time Magazine Archive

All at once he recalled his companion's questions about the air brake pipes the night before.

From The Circus Boys on the Plains : or, the Young Advance Agents Ahead of the Show by Darlington, Edgar B. P.