electron tube

American  

noun

1. an electronic device that consists, typically, of a sealed glass bulb containing two or more electrodes: used to generate, amplify, and rectify electric oscillations and alternating currents.

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electron tube British  

noun

1. Sometimes shortened to: tube.  Also called: vacuum tube.  an electrical device, such as a valve, in which a flow of electrons between electrodes takes place

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electron tube Scientific  

1. A sealed glass tube containing either a vacuum or a small amount of gas, in which electrons move from a negatively charged electrode, the cathode, to a positively charged one, the anode. The cathode is usually heated by an electric current to free the electrons. Other electrodes in the tube can vary the electric or magnetic fields in the tube to control the strength and direction of the moving electrons. Electron tubes are used to amplify signals, rectify AC currents, and produce x-rays, among other uses. They have been mostly replaced by transistors but are still used in television screens, computer monitors, and microwave technology.

2. Also called valve

3. See also vacuum tube

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Etymology

Origin of electron tube

First recorded in 1920–25

Example Sentences

Prosecutors said Mr. Ghahreman conspired to use a Dubai-based front company to help supply the Iranians, including with gyrocompasses used for swift boat navigation and electron tubes used for military airborne radar.

From New York Times

Then, too, the older electron tubes had not been entirely replaced.

From Project Gutenberg

They stepped into a little cell, completely surrounded with mirrors and vast prisms and lenses and electron tubes.

From Project Gutenberg