Boggart-Banishing Spell

The Boggart-Banishing Spell (Riddikulus) is a charm that is used in defence against a Boggart. It causes the creature to assume a form that is humourous to the caster, thereby counteracting the Boggart's ability to terrorise. Boggarts are defeated by laughter, so forcing them to assume an amusing form is the first step to defeating them.

Professor Remus Lupin taught this to his third year Defence Against the Dark Arts class. Thanks to Lupin's teaching, Harry Potter was able to use this against a Boggart in the Triwizard Maze in 1995.

Etymology
"Riddikulus" is an adaptation of "ridiculous" as well as of ridiculum (Latin, "joke") and ridere (Latin, "to laugh").

Appearances

 * Harry Potter and the Prisoner of Azkaban
 * Harry Potter and the Prisoner of Azkaban (film)
 * Harry Potter and the Prisoner of Azkaban (video game)
 * Harry Potter and the Goblet of Fire
 * Harry Potter and the Order of the Phoenix
 * LEGO Harry Potter: Years 1-4

Notes and references
Riddikulus Naurretavus