דברי הימים ב לג:ו פירוש: רש״י

and those who divine by the jidoa bone - Heb. יִדְּעוֹנִי spelled in full with a “vav,” because he did much [evil], and he added to the graven image of the idol that he made. They would take the bone of an animal known as jidoa, and place it in their mouths, whence it would speak.