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thermion

[ thurm-ahy-uh n, -on; thur-mee-uh n ]
/ ˈθɜrmˌaɪ ən, -ɒn; ˈθɜr mi ən /

noun Physics.

an ion emitted by incandescent material.

Nearby words

  1. thermette,
  2. thermic,
  3. thermic fever,
  4. thermidor,
  5. thermidorian,
  6. thermionic,
  7. thermionic current,
  8. thermionic emission,
  9. thermionic tube,
  10. thermionic valve

Origin of thermion

First recorded in 1910–15; therm- + ion
Related formstherm·i·on·ic, adjectivetherm·i·on·i·cal·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for thermion

thermion

/ (ˈθɜːmɪən) /

noun

physics an electron or ion emitted by a body at high temperature
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for thermion

thermion

[ thûr′mī′ən ]

An electrically charged particle or ion that is emitted by a heated conducting material. The electrons emitted from the cathodes of electron tubes (such as cathode ray tubes) are thermions.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.