In Tibetan Buddhism, the Adi-Buddha is the "Primordial Buddha." The term refers to a self-emanating, self-originating Buddha, present before anything else existed. Samantabhadra/Samantabhadri and Vajradhara are Adi-Buddha. Ati Yoga (or Primordial Yoga), which is another name for the Tibetan tradition of Dzogchen, employs an Adi-Buddha sadhana, or practice. NB: Ati and Adi are different orthographic representations of phonemes of the language of Uddiyana which equate to 'primordial' according to Chögyal Namkhai Norbu.