What was the witch called from the Wizard of Oz?

In the movie there was Glenda, the good witch from the south. The Wicked Witch of the West was the famous one, while the wicked witch of the east was disposed of by Dorothy, whom the Munchkins initially revered as a powerful witch herself.

In the book, Dorothy is originally met by the witch of the north, who was not as powerful as the East witch or she would have freed the Munchkins herself.