Accio: The Summoning Charm. When used in connection with an object, this charm will cause such object to fly to the spell caster. It comes in very handy for Harry during the Tri-Wizard Tournament.
Alohomora: A simple spell learned by first-year students that will open most locks — so long as they haven’t been bewitched by a stronger charm.
Amortentia: The most powerful love potion in the world, recognizable by its mother-of-pearl sheen. Amortentia gives off the odors most favored by those who smell it to cast the illusion of passion and affection.
Avada Kedavra (Killing Curse): One of the three so-called “Unforgivable Curses.” Avada Kedavra kills any living being instantly. There is only one known survivor of the Killing Curse, Harry Potter.
Bat-Bogey Hex: A nifty little curse that causes flapping wings to appear on the recipient’s face. Ginny Weasley is very adept at casting Bat-Bogey Hexes, and is in fact rewarded with Professor Slughorn’s attentions for casting one on Zacharias Smith, a snobby fellow student.
Confundus Charm: The spell equivalent of an anvil to the head. A Confunded person is liable to crash into stationary objects and have a tendency to forget his own name. Hermione performs one on Cormac McLaggen, a cocky Gryffindor seventh-year, during Quidditch tryouts in Half-Blood Prince.
Crucio (Cruciatus Curse): The second Unforgivable Curse. The Cruciatus Curse causes its victim excruciating pain and suffering and is used as a torture device by Voldemort and his Death Eaters. Alice and Frank Longbottom, Neville Longbottom’s parents, were tortured by Bellatrix Lastrange into insanity with this curse. They have yet to recover.
Diffindo: Aslicing charm that appears to act like a wizard’s “pocket knife.” Harry used it to cut open Cedric’s bag in Goblet of Fire and also to slice the cover off of his new Spellbook in Half-Blood Prince.
Drought of Living Death Potion: The potion Harry successfully mixes with the help of the Half-Blood Prince to win a bottle of Felix Felicis.
Episkey: A handy spell for repairing minor physical injuries. Tonks uses it to repair Harry’s broken nose in his sixth year.
Evanesco: A vanishing spell. It isn’t exactly clear if the vanished objects disappear permanently — or reappear in a more convenient location.
Expecto Patronum: An incantation to create a Patronus, which usually takes the form of an animal and protects the spell-caster from Dementors.
Expelliarmus: A basic defensive spell first taught by Snape at the Dueling Club meeting in Chamber of Secrets. Its premise is to block or refract an opponent’s spells; however, it can have interesting side-effects when mixed with other incantations.
Felix Felicis: “Liquid luck”. When taken moderately, it offers a “perfect day”: namely, the taker will have luck on his or her side for an entire 12-hour period. Things will just…happen to his or her benefit. However, taken in excess, Felix causes recklessness and silly behavior. It is illegal to use Felix Felicis in sporting events or games of chance.
Impedimentia: A simple stunning spell that often comes in handy for Harry and his friends in tight situations.
Imperius Curse: The last of the Unforgivable Curse. The Imperius Curse allows the caster to take complete control of another person’s mind and body. Think of a living puppet, unable to control his or her thoughts or actions — that is the Imperius Curse.
Levicorpus: A non-verbal spell invented by the Half-Blood Prince, handwritten in Harry’s Potions textbook; the person on whom the spell is cast will be hung upside down by the ankle.
Liberacorpus: The anti-spell to Levicorpus.
Lumos: A simple spell that creates a ball of light at the tip of the caster’s wand.
Mordsmorde: The incantation that causes the Dark Mark to appear in the sky.
Muffliato: A spell invented by the Half-Blood Prince, handwritten in Harry’s Potions textbook; it fills the ears of anyone nearby with an unidentifiable buzzing, so that conversations can be held without being overheard.
Obliviate: The Memory Charm. The victim of this spell will lose some or all of his or her memory, depending on the intent of the caster. It is often used by wizards to help Muggles “forget” magic they have seen or been a party to. Usually, a wizard will replace the erased memory with a much more plausible one.
Polyjuice Potion: A complex potion that takes a month to create and will turn one person into another — as long as the identity thief can get something personal from his or her target’s body, such as a strand of hair, a nail clipping, or a piece of skin. It is brewed and used several times in the Harry Potter books, both by the good guys and the bad.
Prior Incantato: A spell that will force the subject wand to emit a “ghost” of the last spell it cast.
Protean Charm: An advanced charm that, when cast on multiple magical objects, reveals the same information to all those who carry one of those objects. It is used for secret communication. Hermione impressed members of the D.A. in sixth year by casting this spell on gold Galleons so they all could plan meetings.
Riddikulus: Renders a boggart ineffective by making it silly. It requires the power of mind of the spell caster. For example, Neville sees the boggart in Prisoner of Azkaban as Professor Snape, whom he fears. After chanting this spell, “Snape” is rendered ridiculous by dressing him in Mrs. Longbottom’s clothes.
Sectumsempra: Another doozie from the Half-Blood Prince. This spell is not so nice — it slices cuts into the victim wherever the caster’s wand is aimed.
The Unbreakable Vow: A spell that binds a wizard/witch to a promise; when it is made, flames from each person’s wand link together like clasped hands, and a third flame from a Bonder twists around them to bind them together.
Unforgiveable Curses: Three cruel curses illegal in the wizarding world. They include the Imperius Curse, the Cruciatus Curse and the Killing Curse.
Veritaserum: A powerful Truth Potion.
Wingardium Leviosa: A simple levitation spell learned by first years. It is significant in that it plays a part in bonding the friendship between Harry, Ron and Hermione.