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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
Historical Examples
  • Radiofrequency power is supplied to the dee by a vacuum-tube oscillator.

    LRL Accelerators Lawrence Radiation Laboratory
  • He guessed that they were housings for vacuum-tube elevator shafts that led to underground caves.

    The Revolt on Venus Carey Rockwell
  • This glow is conceived to represent the Aurora, which may consequently be likened to a gigantic exhibition of vacuum-tube lights.

    Curiosities of the Sky Garrett Serviss
  • It was only a matter, he said, of transferring a man's habit patterns from brain cells to vacuum-tube cells.

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 In other electronic applications, vacuum tubes have largely been replaced by transistors.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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