Esmeralda "Granny" Weatherwax is one of the recurring heroes of the Discworld series of comedic fantasy books.
A stern, skinny old woman who walks just on the "good" side of the thin line between good witch and bad witch. Thinks she knows what's best for people, and is usually right. Not well-liked, but well-respected, and that's usually good enough for her. Lives in the mountain kingdom of Lancre, and as far as she's concerned she and her fellow witches are the ones who really run the place. Tends to avoid using actual witch-magic unless she actually has to, preferring to use "headology" - her own personal version of psychology - something she is very, very, very good at. She is widely considered to be the most powerful witch on the Disc — even the Feegles call her "The Hag O' Hags."
Trolls call her "Aaoograha hoa" ("She who must be avoided"). Dwarves name her "K'ez'rek d'b'duz" ("Go Around the Other Side of the Mountain").