In the Talmud at Pesachim 110a:14, who is the “Chief of the Witches” that Ameimar refers to?

In the Talmud, a collection of Jewish texts, there is a reference to the “Chief of the Witches” in Pesachim 110a:14. This passage is part of a larger discussion about the use of witchcraft and magic, and it is not entirely clear who the “Chief of the Witches” referred