Arsenius Jigger was a wizard and an author specialising in Potions and Defence Against the Dark Arts, having written Magical Drafts and Potions, Potion Opuscule, and The Essential Defence Against the Dark Arts.
Arsenius is clearly from "arsenious" meaning "containing arsenic", a very poisonous metallic element. A jigger is a liquid measurement, often for liquor, of 1½ fluid ounces (44 millilitres).
- Harry Potter and the Philosopher's Stone (First mentioned)
- Harry Potter and the Prisoner of Azkaban (film) (Name appears on book cover and carved into wood panel)
- Harry Potter Page to Screen: The Complete Filmmaking Journey (Mentioned only)
- Pottermore (Mentioned only)
Notes and references