Definitions for "Solar spectrum"
The electromagnetic spectral distribution emitted by the sun or received by a collector or instrument on Earth. For example, Figure 2 from Shining On below shows the solar spectrum as measured in space and on the Earth's surface.
distribution by wavelength (or frequency) of solar radiation  Sonnen- strahlungs- spektrum
The total distribution of electromagnetic radiant energy over the band of wavelengths present in solar radiation. The total energy received on a given surface, and how that energy is distributed among various wavelengths, depends on how much of the Earth's atmosphere light has traversed.