Hybrid "green" solvent systems composed of room-temperature ionic liquids (ILs) and poly(ethylene glycols) (PEGs) may have enormous future potential. Solvatochromic absorbance probe behavior is used to assess the physicochemical properties of the mixture composed of IL 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim] [PF6]) and PEG (average molecular weights of 200, 400, 600, and 1500) at ambient conditions. Lowest energy intramolecular charge-transfer absorbance maxima of a betaine dye, i.e., E-T(N), indicates the dipolarity/ polarizability and/or hydrogen-bond donating (HBD) acidity of the [bmim][PF6] + PEG mixtures to be even higher than that of neat [bmim][PF6], the solution component with higher dipolarity/polarizability and/or HBD acidity. Dipolarity/polarizability (pi*) obtained separately from the electronic absorbance response of probe N,N-diethyl-4-nitroaniline shows a trend similar to E-T(N) thus confirming the unusually high dipolarity/ polarizability of the [bmim] [PF6] + PEG mixtures. Similar to E-T(N) and pi*, the HBD acidity (a) of [bmim] [PF6] + PEG mixtures is also observed to be anomalously high. Contrary to what is observed for E-T(N), pi*, and alpha, the hydrogen-bond accepting (HBA) basicity (8) of the [bmim][PF6] + PEG mixtures is observed to be lower than that predicted from ideal additive behavior indicating diminished HBA basicity of the mixture as compared to its neat components. A four-parameter simplified combined nearly ideal binary solvent/ Redlich-Kister (CNIBS/R-K) equation is shown to satisfactorily predict the solvatochromic parameters within [bmim] [PF6] + PEG mixtures. It is demonstrated that [bmim] [PF61 + PEG mixtures possess physicochemical properties that are superior to those of either the neat IL or the neat PEG.