therm·​ion·​ics ˌthər-(ˌ)mī-ˈä-niks How to pronounce thermionics (audio)
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

Dictionary Entries Near thermionics

Cite this Entry

“Thermionics.” Dictionary, Merriam-Webster, Accessed 16 Jun. 2024.

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