Langlock

From Harry Potter Wiki

Langlock
Incantation:	LAN-glock
Type:	Jinx
Effect:	Affixes tongue to the roof of the mouth

Langlock is a jinx or hex that causes one's tongue to affix to the roof of the mouth. It was invented by Severus Snape while he was a student at Hogwarts School of Witchcraft and Wizardry.

Harry Potter used Langlock on Argus Filch, and again on Peeves.

[edit] Etymology

The word langue is the root for tongue.