- a brake or system of brakes operated by compressed air.
- Aeronautics. a device for reducing the air speed of an aircraft by increasing its drag.
- a device for stopping the sails of a windmill by disrupting the flow of air around them.
Origin of air brake
An Americanism dating back to 1870–75
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for air brake
There was perfect silence but for the pumping of the air-brake on the engine.Red Men and White
Page 57, changed "air-brakes consists" to "air-brake consists."How to Become an Engineer
Frank W. Doughty
Callahan was seventeen, with hair like a sunset, and a mind quick as an air-brake.The Nerve of Foley
Frank H. Spearman
Written by an Air-Brake Instructor who knows just what is needed.
Endorsed and used by air-brake instructors and examiners on nearly every railroad in the United States.
- a brake operated by compressed air, esp in heavy vehicles and trains
- Also called: dive brake an articulated flap or small parachute for reducing the speed of an aircraft
- a rotary fan or propeller connected to a shaft to reduce its speed
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012