Locking Spell

"'Colloportus!' gasped Hermione and the door sealed itself with an odd squelching noise."

- Hermione Granger's use in the Battle of the Department of Mysteries

The Locking Spell (Colloportus) is a charm that is used to lock or seal doors so that they cannot be opened manually; however, it is unknown whether a key could be used to unlock them. If it is true that a key would be ineffective against a door sealed with this spell, it would prove quite useful against Muggles because there is a well-known counter charm, Alohomora.

Uses

 * The charm is featured in The Standard Book of Spells, Grade 1.
 * Hermione Granger and Harry Potter both used this spell in the Battle of the Department of Mysteries, although the latter's attempts were mostly unsuccessful.
 * Severus Snape may have used this spell to close and lock the unusually small door behind his bookshelf in order to prevent Peter Pettigrew overhearing his conversation with Narcissa Malfoy and Bellatrix Lestrange in 1996.

Possible uses

 * This may have been the spell that Albus Dumbledore used to magically lock the door to the Hospital wing after Harry and Hermione returned from rescuing Sirius Black in 1994.

Behind the scenes
"It appears to be some sort of locking charm"

- Harry Potter on the spell used on the doors


 * In the second video game adaption of Harry Potter and the Deathly Hallows during the 1998 Break-in of Gringotts Wizarding Bank Harry Potter, Ronald Weasley and Hermione Granger found a lot of doors was magically sealed by "some sort of locking charm" and Hermione had to use the Unlocking Charm. This Locking Spell is possibly the one mentioned as it locks a door and is a charm.

Etymology
Colloportus is composed of the prefix "collo-" deriving from Latin colligo meaning to bind together or possibly Greek κολλάω, κολλώ (collo) which means "to glue, stick" and Latin portus meaning door.

Appearances

 * Harry Potter and the Prisoner of Azkaban
 * Harry Potter and the Order of the Phoenix
 * Harry Potter and the Half-Blood Prince (film)
 * Harry Potter and the Deathly Hallows: Part 2 (video game)
 * Pottermore