|"We must've been through hundreds of books already and we can't find him anywhere —"|
Hornby was the surname of a family with at least one magical member.
- Olive Hornby — a witch who attended Hogwarts School of Witchcraft and Wizardry in the 1940s.
- Hornby — Olive's brother.
The surname Hornby comes from the name of several places in northern England, which derive from a combination of the Old Norse given name Horni, meaning "horn", and the Old Norse word býr, meaning either "farm" or "settlement".