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vacuum tube

noun

: an electron tube evacuated to a high degree of vacuum

Examples of vacuum tube in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The intent of their research effort was to develop a technology to replace vacuum tubes that powered communications networks. Scott D. Anthony, Fortune, 29 Nov. 2025 The idea isn't new, but Epirus has improved on previous iterations by using Gallium Nitride (GaN) semiconductors to generate microwaves instead of fragile, power-hungry magnetron vacuum tubes. New Atlas, 27 Sep. 2025 This package includes the motor, blower and vacuum tubes, concentrator nozzle and a leaf collection bag. Bestreviews, Mercury News, 26 Sep. 2025 Photos: Jayme Thornton Indeed, an ionization gauge has the same basic components as a vacuum tube. IEEE Spectrum, 24 Sep. 2025 See All Example Sentences for vacuum tube

Word History

First Known Use

1859, in the meaning defined above

Time Traveler
The first known use of vacuum tube was in 1859

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Cite this Entry

“Vacuum tube.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/vacuum%20tube. Accessed 7 Dec. 2025.

Kids Definition

vacuum tube

noun
: an electron tube from which most of the air has been removed

Medical Definition

vacuum tube

noun
: an electronic device in which conduction by electrons takes place through a vacuum within a sealed glass or metal container and which has various uses based on the controlled flow of electrons

More from Merriam-Webster on vacuum tube

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