I read your answer Jacqui, and bells were ringing in my memory, of the sound of the word that you spell pishogue.
Somewhere I have read the word "piseog" in the context of Celtic magics. It would sound almost the same.
So I searched and found this-
"The Irish word Fáith means Seer or one who has the Second Sight i.e. the ability to communicate with the dead and even the power of prophesy. These folks were also known as Piseog (witch) who practiced Piseogacht or witchcraft. The Piseog/Fáith was a local healer, wise or cunning person, and philosopher."
Cheers
Dave