Lacarnum Inflamari

Lacarnum Inflamari is the incantation of a charm used to ignite the cloak of a witch or warlock by shooting a fireball from the tip of the caster's wand.

Hermione Granger was known to be proficient in the performing of this spell, using it in September of 1991 on her Potions Master, Professor Severus Snape, at a Quidditch game when she believed him to be jinxing her friend Harry Potter's broomstick.

Etymology
The incantation "Lacarnum Inflamari" appears to be derived from the Latin "lucerna", a meaning "cape" or "cloak" and "inflammo", a  meaning "torch" or "inflame".

Behind the scenes

 * This spell only appears in the very first film; in the book, Hermione uses Bluebell Flames.
 * It is currently unknown if this charm would work to repel Lethifolds and Dementors; one could presumably use this to burn the creature's cloak.

Author's comments
"Some of the new incantations, such as ‘lacarnum inflamari’ must have sounded more dramatic onscreen – although by the time you’ve managed to say ‘lacarnum inflamari’, you’ve surely lost precious seconds in which the Devil’s Snare might have throttled you. But that’s showbiz."

Appearances

 * Harry Potter and the Philosopher's Stone (film)
 * LEGO Harry Potter: Years 1-4

Notes and references
Lacarnum Inflamarae Lacarnum Inflamari