therm·​ion·​ic ˌthər-(ˌ)mī-ˈä-nik How to pronounce thermionic (audio)
: relating to, using, or being the emission of charged particles (such as electrons) by an incandescent material

Examples of thermionic in a Sentence

Recent Examples on the Web The new thermionic cooler from Prunnila and his colleagues is built to control phonon flow. IEEE Spectrum, 12 Sep. 2023 The new coolers fall into the class of thermionic devices, which shed heat in the form of electrons. IEEE Spectrum, 12 Sep. 2023 The thermionic diode heat engine invented by Nottingham and Hatsopoulos in the 1950s finally went all the way and produced power with no moving parts. Charles A. Berg, The New York Review of Books, 6 June 2019

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'thermionic.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


thermion charged particle from an incandescent source, from therm- + ion

First Known Use

1909, in the meaning defined above

Time Traveler
The first known use of thermionic was in 1909

Dictionary Entries Near thermionic

Cite this Entry

“Thermionic.” Dictionary, Merriam-Webster, Accessed 1 Dec. 2023.

Last Updated: - Updated example sentences
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