The basic meaning of the shabad Apras is “which can’t be touched by Maya.” The Shabad and Surat must combine inside a person to make them into an Apras soul.  Shabad and Surat only combine with the GurParsaad of a Puran Brahamgiani.  When they combine it transforms an ordinary soul into a ParGhatyeo Jyot Puran Brahamgiani and such a soul has been called Apras.  Derived from "Paras Pathat".