solar constant solar collector • solar day · · · Info · Definitions · Characters · · solar constant · · Text Common · · Latin · · Scripts 14 · · Length 4 · · Syllables Definitions · · · (noun) the rate at which radiant solar energy is received at the outer layer of the earth's atmosphere. Synonyms: solar constant. · · Noun Definition 1 Characters · · space U+0020 a latin small letter a U+0061 c latin small letter c U+0063 l latin small letter l U+006C 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