thermionics

noun

therm·ion·ics ˌthər-(ˌ)mī-ˈä-niks

plural in form but singular in construction

: physics dealing with thermionic phenomena

Word History

First Known Use

1909, in the meaning defined above

Time Traveler

The first known use of thermionics was in 1909

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Style

“Thermionics.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thermionics. Accessed 6 Dec. 2025.

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