Stokes type radiation

https://doi.org/10.1351/goldbook.S06032
fluorescence radiation occurring at wavelengths longer than absorption, i.e. the normal case, is said to be of the Stokes type.
Source:
PAC, 1984, 56, 231. 'Nomenclature, symbols, units and their usage in spectrochemical analysis-Part VI: molecular luminescence spectroscopy' on page 236 (https://doi.org/10.1351/pac198456020231)