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.
Arthur Richardson founded the company in 1947 to sell surplus military vacuum tubes to the fledgling television and radio industries. — John Lippert, Chicago Tribune, 14 Oct. 2026 Conventional radiation monitors have long relied on traditional glass vacuum tubes. — Aman Tripathi, Interesting Engineering, 7 Oct. 2026 The underwater robot couldn’t lift the rock, but the robot was equipped with a vacuum tube. — Encyclopedia Britannica, 25 Aug. 2026 Unsurprisingly, this took a few attempts to get right—resulting in three vacuum tubes exploding. — Andrew Paul, Popular Science, 23 July 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 20 Oct. 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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