- "...Bagman pointed his wand at his throat and muttered 'Quietus'."
- —Ludo Bagman's use on himself[src]
Quietus is the counter-spell to of Sonorus, the incantation which amplifies a person's voice. This spell was used by Ludo Bagman at the Quidditch World Cup in 1994. Lord Voldemort most likely used this spell to counter his Sonorus.
Latin quietus, "calm" or "quiet".