[thurm-ahy-uh n, -on; thur-mee-uh n]
- an ion emitted by incandescent material.
Origin of thermion
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- physics an electron or ion emitted by a body at high temperature
- 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.
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