Simple Definition of vacuum tube

from our Learner's Dictionary

vacuum tube

noun

plural vacuum tubes
US : a glass tube that was used in the past in computers, televisions, etc., to control the flow of electricity

called also (British) valve

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“Vacuum tube.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/vacuum%20tube. Accessed 22 Jun. 2026.

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