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 transistors were smaller, used less power and generated less heat than previous vacuum tubes. — Christopher Howley, AZCentral.com, 23 Dec. 2025 Officials say the same core technology could eventually support space launch systems and vacuum tube transport concepts. — Sujita Sinha, Interesting Engineering, 26 Dec. 2025 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 students installed 500 simulated vacuum tubes in each of the panels here, for a total of 18,000 vacuum tubes. — IEEE Spectrum, 30 Apr. 2026 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

Rhymes for vacuum tube

See All Rhymes for vacuum tube

Browse Nearby Words

vacuum tank
vacuum tube
vacuum-tube voltmeter
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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 Jul. 2026.

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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

Britannica.com: Encyclopedia article about vacuum tube

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