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vacuum tube

Also called, especially British, vacuum valve. an electron tube from which almost all air or gas has been evacuated: formerly used extensively in radio and electronics.
a sealed glass tube with electrodes and a partial vacuum or a highly rarefied gas, used to observe the effects of a discharge of electricity passed through it.
Origin of vacuum tube
1775-85 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for vacuum tube
  • These new computers will eventually make a stand-alone desktop system look as anachronistic as the vacuum tube.
  • vacuum tube hardware weighing hundreds of kilograms is needed to produce the highest-power signals for military radar.
  • They are coupled to opposite ends of the same motor, the speed of which is held constant by means of a vacuum tube regulator.
  • Xenon in a vacuum tube produces a beautiful blue glow when excited by an electrical discharge.
  • In electronics, the basic technology was the vacuum tube.
  • The clay is then fed into an auger, which moves the clay down the trough and into a vacuum tube.
British Dictionary definitions for vacuum tube

vacuum tube

another name for valve (sense 3)
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
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vacuum tube in Science
vacuum tube  
An electron tube from which all air has been removed. The vacuum ensures transparency inside the tube for electric fields and moving electrons. Most electron tubes are vacuum tubes; cathode-ray tubes, which include television picture tubes and other video display tubes, are the most widely used vacuum tubes. In other electronic applications, vacuum tubes have largely been replaced by transistors.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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vacuum tube in Technology
The Free On-line Dictionary of Computing, © Denis Howe 2010
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