Ìyáláwò ('mother of secrets') and ìyánífá ('mother of Ifá') name a woman who is initiated in Ifá and may work with the oracle; the words are used of the female counterpart of the babalawo, though the offices are not symmetrical in every house. The tradition also recognises àpètèbí, women whose relationship to Ifá is one of service and support to a priest rather than of casting, and ìyálọ̀ṣà, priestesses of an orìṣà who are not Ifá priests at all. Which of these a woman may be is the sharpest institutional difference in the whole system.