The news had traveled very fast: Apparently Moaning Myrtle had taken it upon herself to pop up in every bathroom in the castle to tell the story; Malfoy had already been visited in the hospital wing by Pansy Parkinson, who had lost no time in vilifying Harry far and wide, and Snape had told the staff precisely what had happened.
There are no more uses of "vilify" in the book.
Show samples from other sources
The Nazi propaganda vilified the Jews.
Vampyres have speculated for centuries that the ecstasy of blood drinking is the key reason humans have vilified our race.