Tergikleen is like Kodak Foto Flow, a wetting and flow aid, non detergent.
Actually, both are nonionic surfactants which at low concentration reduce the surface tension of water ergo wetting. But at higher concentrations, nonionic surfactants act as emulsifying agents (breakup oil); ergo a form of detergency. Tergikleen at the manufacturers recommended concentration will acts as both a wetting agent and as a detergent (oil emulsification). But these are nothing like Dawn which is very different and is most people's perspective of a detergent.