thermionics thermionic emission • thermionic tube · · · Info · Definitions · Characters · · thermionics · · Text Latin · · Script 11 · · Length 3 · · Syllables Definitions · · · (noun) the branch of electronics dealing with thermionic phenomena (especially thermionic vacuum tubes). · · Noun Definition 1 Characters · · c latin small letter c U+0063 e latin small letter e U+0065 h latin small letter h U+0068 i latin small letter i U+0069 m latin small letter m U+006D n latin small letter n U+006E o latin small letter o U+006F r latin small letter r U+0072 s latin small letter s U+0073 t latin small letter t U+0074