1 definition by Lizzi K
The name in the Harry Potter wizarding world for Lord Voldemort. He has also been called "He Who Must Not Be Named", "Lord Thingy", and other appellations of the sort.
Ron: "Hey, Hermione, I heard that You-Know-Who is trying to find Harry. D'you think he wants to kill him?"
by Lizzi K March 31, 2006