Accio! (Goblet of Fire, page 68)
Etymology: L. accedo (to approach, come near / (things) to be added).
The Summoning Charm (incantation: "Accio!") is used to bring an object to you, wherever it may be. Concentrating is essential to succeeding in the spell; the further away an object is and the larger it is, the harder it is to summon. The two most difficult Summoning Charms are in Goblet of Fire and Order of the Phoenix. In Goblet of Fire, Harry summons his Firebolt from inside the castle to the grounds to use it for the first task of the Triwizard Tournament. In Order of the Phoenix, the potency of the charm is demonstrated when Fred and George Weasley summon their brooms (which were chained to a wall) from another part of the castle.
Aguamenti! (Half-Blood Prince, page 574)
Etymology: L. Agua (water) + Mentis (Mind).
"Aguamenti!", which is taught in the sixth year, is a spell whose affect is a clear jet or fountain of water being emitted from the castor’s wand.
Alohomora! (Sorcerer's Stone, page 160)
Etymology: Hawaiian. Aloha (goodbye) L. + mora (delay)
The Alohomora Charm (incantation: "Alohomora!") is used to unlock doors or other objects that are locked. The charm also unlocks magically locked doors or objects (see "Colloportus!"). Though the charm comes in handy for Harry, Hermione, and Ron throughout the books, it is not powerful. As shown in Chapter 34, "The Department of Mysteries," in Order of the Phoenix, The Alohomora Charm does not unlock all magically locked doors or objects.
Anapneo! (Half-Blood Prince, page 144)
Etymology: Greek. Anapneo (Breathe).
A useful spell that clears the blocked airway of the castor’s target. Slughorn uses the spell to save a student's life.
Aparecium! (Chamber of Secrets, page 233)
Etymology: L. appareo (to become visible, appear, manifest).
"Aparecium!" is used only once by Hermione in an attempt to reveal the hidden contents of Tom Riddle's diary. Though the spell is unsuccessful, Hermione says that it is used to reveal invisible ink.
Avada Kedavra! (Goblet of Fire, page 215)
Etymology: Aramaic. abracadabra (ancient spell meaning "let the thing be destroyed")
The Killing Curse (incantation: "Avada Kedavra!") is considered by most wizards the worst curse, as it kills whoever or whatever it is cast upon. The curse is one of three Unforgivable Curses - curses that are illegal and can land a wizard in Azkaban Prison for using them (see "Imperio!" and "Crucio!").
Crucio! (Goblet of Fire, page 214)
Etymology: L. crucio (to torture, torment)
The Cruciatus Curse (incantation: "Crucio!") inflicts severe pain on whoever it is cast on. It is used mainly by Voldemort and his Death Eaters when torturing someone. Rowling describes the pain as this: "White-hot knives were piercing every inch of his skin, his head was surely going to burst with pain, he was screaming more loudly than he'd ever screamed in his life..." The length of time the curse is in effect is unknown, but it is presumed to stop after 15 seconds - 1 minute. Wizards and witches (i.e. Frank and Alice Longbottom) can be tortured to the point of insanity by the curse. This explains why the Cruciatus Curse is one of three Unforgivable Curses - curses that are illegal and can land a wizard in Azkaban Prison for using them (see "Avada Kedavra"! and "Imperio!").
Expecto Patronum! (Prisoner of Azkaban, page 238)
Etymology: L. exspecto (to wait for, look for, expect), + patronus (patron, protector)
The Patronus Charm (incantation: "Expecto Patronum!") is highly advanced magic, well beyond the Ordinary Wizarding Level, used to ward off dementors. When used properly, the spell creates a Patronus, which is a guardian that acts as a shield between the caster and the dementor. Each Patronus is unique to the wizard or witch who conjures it, and reflects their personality. In order for the spell to work properly, the incantation must be spoken while the caster concentrates on a extraordinarily happy memory. This causes a Patronus to be conjured; it is successful in warding off dementors because it is "a projection of the very things that the dementor feeds upon - hope, happiness, the desire to survive - but it cannot feel despair, as real humans can, so the dementors can't hurt it." (Prisoner of Azkaban, page 238)
Expelliarmus! (Chamber of Secrets, page 190)
Etymology: L. expello (to drive out, expel, force out, banish)
The Disarming Charm (incantation: "Expelliarmus!") is used to disarm someone, and is most commonly used while dueling. Though a simple spell, it can be used to get wizards and witches out of tight situations and close encounters - it saved Harry Potter's life in Goblet of Fire.
Impedimenta! (Goblet of Fire, page 626)
Etymology: L. impedimentum (hindrance, impediment, obstacle, difficulty)
"Impedimenta!" slows down an attacker. If the spell is cast upon armor or other metal objects, it will backfire. If the spell is cast upon someone who is standing still, the person standing still will either freeze and be unable to move until they are "unfrozen" or will be knocked off of their feet.
Imperio! (Goblet of Fire, page 214)
Etymology: L. imperium (power to command, authority, command, rule, control)
The Imperius Curse (incantation: "Imperio!") is used to control the actions of a person. Although few have the willpower to resist the curse, many wizards and witches cannot. Because wizards can completely control the actions of others when they are under this curse, it is one of the three Unforgivable Curses - curses that are illegal and can land a wizard in Azkaban Prison for using them (see "Avada Kedavra!" and "Crucio!").
Legilimens! (Order of the Phoenix, page 534)
Etymology: L. lego (to gather, choose, collect, pass through, read) + mens (mind)
"Legilimens!" is mostly used by accomplished Legilimens, those who can read minds. The spell is used when attempting to break into someone else's mind and access their memories - usually memories that they fear.
Levicorpus! (Half-Blood Prince, page 238)
Etymology: L. Levo (To lift up) + Corpus (Body)
Invented by Severus Snape, this spell dangles the victim upside down in the air by his/her ankle.
Lumos! (Chanber of Secrets, page 302)
Etymology: L. luma (light)
"Lumos!" is one of the most commonly used spells, because it is a simple spell and useful. As its Latin root implies, "Lumos!" causes a light to appear at the end of the wand that cast the spell. The incantation "Nox!" is spoken when the bearer of the wand wishes for the light to go out.
Nox! (Prisoner of Azkaban, page 338)
Etymology: L. nox (darkness)
"Nox!" is used to put out the light created by "Lumos!" The spell presumably does nothing to the caster's wand if "Lumos!" has not previously been cast. The use of the spell on lit objects which are disconnected from the caster's wand is unknown.
Reparo! (Goblet of Fire, page 169)
Etymology: L. reparo (to restore, renew)
"Reparo!" does exactly what its Latin root suggests - fixes things that are broken. Examples in the Harry Potter books include fixing broken glass, broken china, broken jars, and broken cups. "Reparo!" only works on solid objects.
and many more
from:veritaserum.com
