HAGGWITCH
A gross, old, mean lady (hag) who has the power (witch) to make your life a nightmare just for fun.
My neighbor is a haggwutch. She turned my dog into a chicken.
My teacher is a haggwutch. She gave me a 100% on a test just to annoy me.
My mom is a haggwutch. She made my dinner taste like a dead rat.