action spectrum action sermon • action-taking · · · Info · Definitions · Characters · · action spectrum · · Text Common · · Latin · · Scripts 15 · · Length 4 · · Syllables Definitions · · · (noun) the efficiency with which electromagnetic radiation produces a photochemical reaction plotted as a function of the wavelength of the radiation. Synonyms: action spectrum. · · Noun Definition 1 Characters · · space U+0020 a latin small letter a U+0061 c latin small letter c U+0063 e latin small letter e U+0065 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 p latin small letter p U+0070 r latin small letter r U+0072 s latin small letter s U+0073 t latin small letter t U+0074 u latin small letter u U+0075