It's called Dracorex Hogwartsia and it means 'Dragon King of Hogwarts.' It's a dinosaur that is only known from a nearly complete skull discovered in Sioux City, Iowa. The skull was donated to the Children's Museum of Indianapolis for study in 2004. Although its existence may be in peril upon further study, because some researchers think that the dinosaur is just a juvenile specimen of another species.
The name itself was inspired by the young visitors of the children's museum. It's a tribute to dragon because Dracorex means dragon king, and the Harry Potter series of books. JK Rowling commented on the development and said she was thrilled that Hogwarts had made a small mark upon the fascinating world of dinosaurs.
Read more about this species here.