Expelliarmus

• Incantation: Expelliarmus
• Pronunciation: eks-PELL-ee-ARE-muss
• Wand Movement: Unknown.
• Light: A jet of scarlet light.
• Effect: Forces whatever the target is holding (most commonly a wand) to fly out of their hand. When multiple spells are cast at once, or when cast with sufficient power, it can exert a strong physical force, capable of knocking a person off their feet or rendering them unconscious.
• Type: Charm (known as the Disarming Charm).

The Disarming Charm is a fundamental dueling spell, and it became the signature spell of Harry Potter. Its use is a recurring and pivotal element throughout the series. The spell is first introduced during a Dueling Club meeting organized by Gilderoy Lockhart at Hogwarts. Severus Snape easily uses it to disarm Lockhart, demonstrating its effectiveness. Harry Potter later uses the spell to disarm Lockhart in the Chamber of Secrets before the professor can wipe his and Ron Weasley's memories. In Harry Potter and the Prisoner of Azkaban, Harry, Ron, and Hermione Granger cast Expelliarmus simultaneously on Snape in the Shrieking Shack; the combined force of the three charms knocks him out cold. This event highlights the spell's ability to produce a powerful concussive blast when amplified. During Harry's duel with Lord Voldemort in the Little Hangleton graveyard, his use of Expelliarmus against Voldemort's Avada Kedavra triggers the rare magical effect of Priori Incantatem, as their wands share a core from the same phoenix, Fawkes. Expelliarmus was the first spell Harry taught to the members of Dumbledore's Army, emphasizing its importance as a non-lethal defensive tool. During the Battle of the Department of Mysteries, Harry and his friends use it frequently against the Death Eaters. A crucial turning point occurs when Draco Malfoy uses Expelliarmus to disarm Albus Dumbledore on the Astronomy Tower. This act, while not fatal, makes Draco the master of the Elder Wand, a fact that later becomes central to the plot. During the Battle of the Seven Potters, Harry's use of his signature spell to disarm a cursed Stan Shunpike immediately identifies him to the Death Eaters, as Voldemort had predicted Harry would rely on it. Remus Lupin later chastises Harry for this, noting that using his “trademark” spell made him easy to recognize. In the final confrontation, Harry's unwavering belief in the power of Expelliarmus leads to his victory. He casts it against Voldemort's Avada Kedavra. Because Harry is the true master of the Elder Wand, the wand refuses to kill him; instead, Harry's Expelliarmus overpowers Voldemort's killing curse, causing it to rebound and kill Voldemort himself.

Expelliarmus is considered a basic defensive spell, suitable for second-year students to learn. It is a staple of practical Defence Against the Dark Arts education. The most common defense against the Disarming Charm is a Shield Charm (Protego), which can block the jet of light. Quick reflexes, such as ducking or dodging the spell, are also effective. A strong grip on one's wand can offer some resistance, but it is generally not enough to overcome a well-cast charm.

The incantation is derived from two Latin words:

• Expellere, meaning “to drive out” or “to expel.”
• Arma, the plural form of armum, meaning “weapon.”

Combined, Expelliarmus literally translates to “drive out the weapon,” a perfect description of the spell's function.

• In an interview, J.K. Rowling stated that Harry's use of Expelliarmus in his final duel with Voldemort represents the core of his character. It shows that he has come to “full maturity” and remains true to himself, choosing to disarm rather than kill. (J.K. Rowling interview)
• In the film adaptations, the visual effect of Expelliarmus is often more dramatic than the simple disarming described in the books. It frequently sends the target flying backward with considerable force, even when cast by a single witch or wizard. (film)
• The final duel between Harry and Voldemort in Harry Potter and the Deathly Hallows: Part 2 depicts the two spells meeting and struggling in mid-air, rather than the instant rebound described in the novel. (film)
• Expelliarmus is a primary combat spell available to the player in most *Harry Potter* video games. (video game)