Tattypoo is the white-haired Good Witch of the North in The Muppets' Wizard of Oz. As played by Miss Piggy, she is very fond of the Munchkins and likes to drop in for a cuddle or two. She also seems to be fond of penguins.
In L. Frank Baum's original novel, The Wonderful Wizard of Oz, the Good Witch of the North is unnamed. In the stage play adaption from 1902, Baum himself named her "Locasta", but this name has not been used outside the stage play, not even in the following "Oz" novels (where she only makes occasional appearances and then almost always as a very minor character). In the 22nd Oz book, The Giant Horse of Oz by Ruth Plumly Thompson, she is finally given the name "Tattypoo".
In the popular MGM movie based on the novel, the Good Witch of the North was eliminated entirely, and her role was merged with that of Glinda.