thermionic emission thermionic current • thermionics · · · Info · Definitions · Synonyms · Characters · · thermionic emission · · Text Common · · Latin · · Scripts 19 · · Length 6 · · Syllables Definitions · · · (noun) the emission of electrons from very hot substances. Synonyms: thermionic emission, thermal emission. · · Noun Definition 1 Synonyms · · · thermal emission · · Synonym 1 Characters · · space U+0020 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