[thurm-ahy-on-iks, thur-mee-]

noun (used with a singular verb)

the branch of physics that deals with thermionic phenomena.

Origin of thermionics

First recorded in 1925–30; see origin at thermion, -ics Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for thermionics



(functioning as singular) the branch of electronics concerned with the emission of electrons by hot bodies and with devices based on this effect, esp the study and design of thermionic valves
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