Another magic trope that is Older Than Dirt, the idea of words that hold magic power unto themselves has been around since Ancient Egypt. Often paired and sometimes lumped with the power of True Names, words of power are common parts of a wizard's bag of tricks.
Words of Power may be a part of a Language of Magic but are distinct in several ways.
Words of power have fairly rigidly defined effects. With the Language of Magic you can write spells while words of power are the spell.
While words of power may be part of a Language of Magic, it is not always so, or if they are it may not be explicitly said to be so, or the language in question may be a lost or fragmented one.
The Lotis and Maram Words from Yuu Watase's manga Alice 19th.
A more literal version of this is in Six Six Six Satan where the character Spika has an O-Part that can materialize words she shouts into them that are like what she says (for example, when she yells "Spikey" the word "Spikey" in Japanese will appear in block letters with spikes coming out).
In the 12th movie of Dragon Ball Z, Pikkon finds out that the hold that Janemba, the reality-warpingBig Bad, has over the afterlife is weakened by harsh words. So after he releases Enma Daiou, he joins Goku and Vegeta in the battle, and holds Janemba off by cursing at him, breaking apart his face, then firing ki blasts at him.
In the 4th part of JoJo's Bizarre Adventure, the character Koichi gets various forms of this as his stand power. What happens is that if his stand hits another person words get written on him or her which start to call out whatever the word is in an increasing volume. Next is when he makes a word and throws it onto something if someone touches the word the effect will take place. (Touching the word Whooosh blows someone away, touching Burn cause someone to catch on fire, and touching Bounce will cause someone to bounce off of whatever the word is one regardless of how sharp the object is normally without harm.
In part 7, the character Sandman gets a similar Stand, though his also seems to be contagious. It's exactly as confusing as it sounds.
In the anime (and original manga) Loveless, characters participate in Spell Battles where words do exactly what they say, restraining, cutting, burning, or banishing opponents. The effectiveness of an attack seems to be directly related to the floweriness or complexity of the spoken "spell".
In YuYu Hakusho, one psychic has the ability to create a territory in which no one can say a taboo word. Anyone who does has their soul ripped out.
Before that, it was shown that there are spells based on chanting which will backfire on the caster if the target doesn't hear the words being said.
Levy and Fried in Fairy Tail have this power, except their words must be written rather than spoken. Levy writes in English, while Fried writes in a made up rune language. As a result Levy's effects are simple but quick (instantly create a block of metal, or a trap hole, or fire, or wind) while Fried's are complex ("Nobody in this space can use magic." "Nobody can leave the space until everyone else has been defeated") but take time to set up. Levy later learns Fried's language, giving her the ability to rewrite his spells to cancel or change their effects.
Elite Mook Yomazu can to this as well, only he writes his in Japanese with his sword. As a result he can abruptly change the effect without rewriting simply by declaring a different meaning of the Kanji.
The Words of Awakening in Madlax, which induce homicidal insanity.
Skuld from Ah! My Goddess gains the ability to forcefully "print" her words on people or things. While not very powerful, it appears to involve enough force to stagger people. Both Urd and Keiichi are frequent victims of this, with Skuld's favorite insults for them being "idiot" and "pervert", respectively.
This appears several times in A Certain Magical Index. In its first form, magicians must first state their magic name to begin using their actual magic. We later see Index in her Johan's Pen mode utter the words "Eli Eli Lama Sabachthani?" literally "God, God, why have you forsaken me?" to power up a spell specifically to destroy Stiyl's Flame Summon. Towards the end, this trope is again invoked when Index interferes with the control spells in place on a golem simply by uttering English letters in certain sequences. This scene also borders on a Crowning Moment Of Awesome.
An interesting variation in Mx0: Fumi Izuno's magic object is a calligraphy brush, and her ability is that everything she writes with it acquires reality. For example, in the last Magic Class Match, she and another student are seen fighting a golem, and in a given moment, she writes the word "Defense" in the air with her brush; the words immediately turn into a magic shield that stops one of the golem's fists in front of her.
Arias can kill lesser demons in Blue Exorcist by reciting a "Fatal Verse", a segment from the bible and other holy scriptures. The problem is that there is a different verse for each type of demon (thus you must memorize which verse kills who), and the Aria becomes defenseless until finishing reciting.
Kotoha from Yozakura Quartet can create any object, as long as she knows what it's made of, with her words. And she is a MASSIVE fan of WWII Weaponry.
Played literally in Bo Bo Bo Bo Bo Bo Bo—the Cyber Knight Poet can use attacks that come from flying kanji he summons, which spells out the attack name.
Medaka Box: This seems to be the concept behind the "styles"; by utilizing wordplay, puns, metonymies, and other ways of manipulating words, the users can potentially manipulate or damage anyone. This includes the Invincible Villain Ihiko
Not exactly words per se, but the Anti-Life Equation in the DC Universe removes the free will of anyone who hears it. During Final Crisis, Darkseid uses it in a terrifying manner when he enslaves three billion people at once.
It's revealed that the Anti-Life Equation goes as follows: Loneliness + Alienation + Fear + Despair + Self-worth ÷ Mockery ÷ Condemnation ÷ Misunderstanding x Guilt x Shame x Failure x Judgment, n=y where y=Hope and n=Folly, Love=Lies, Life=Death, Self=DARKSEID. Darkseid actually modified the Equation. Originally, Self=Nothing.
In Superman and Batman: World's Funnest, where Bat-Mite and Mr. Mxyzptlk fight their way through the DC Multiverse, Darkseid finds the equation is in fact Bat-Mite + Mxy. He startslaughing...
In the Douwe Dabbert story The Witches of the Day Before Yesterday, the dark dunes are controlled by three witches who keep saying "Wij zijn niet van gisteren" ("We weren't born yesterday"). Finally, Douwe figures it all out and declares that they were born the day before yesterday, turning the witches into salamanders.
In Ex Machina, Mitchell's powers work like this, as do Pherson's and Suzanne's.
Zatanna can do just about anything by reciting words and sentences backwards. Her cousin Zatarra can also do this although he can't directly affect living things.
Nico from Runaways can use the Staff of One to create any magical effect she can describe (usually in one or two words). However, each description can only be used once. However, she can get the same effect more than once by using synonyms and different languages.
The 1984 film adaptation of Dune turns the "Weirding Way" from a super-powered martial art into a method of using words as a weapon, with technological assistance. It took Paul's line "My name is a killing word" and made it literal: saying "Muad'Dib" while holding one of the "Weirding Modules" converts the sound into a sonic blast.
In the novel, one of the powers of the Bene Gesserit is the Voice, a manner of speaking that can compel obedience from a person that the speaker understands sufficiently. Paul, being the Kwisatz Haderach, develops this ability to the point where he can indeed kill with it, and threatens to use it on the Reverend Mother Mohiam during the climax unless she stops opposing him.
Monty Python and the Holy Grail: The Knights Who Say Ni, keepers of the sacred words "Ni", "Peng", and "Neee-Wom", which appear to cause unbearable agony (or at least mild discomfort) to those who hear them.
And are themselves hurt by the word "it".
Bibbidi-Bobbidi-Boo - the magic words of the Fairy Godmother in Disney's Cinderella.
Bedknobs and Broomsticks give us the spell of Substitutiary Locomotion ("giving life to things without"): Treguna Mekoides Trecorum Satis Dee. Which sounds ''really' creepy when the things the spell animates (like empty suits of armor) start repeating it...
In the silent movie The Golem, it is a scroll inscribed with a magic word (Aemaet) that brings the Golem to life. This is consistent with the traditional Golem lore.
David EddingsThe Redemption of Althalus, where the Books of Deiwos and Daeva are the source of the good guys' and the bad guys' magic respectively. Fun fact: the words themselves are Proto-Indo-European.
In his Belgariad/Mallorean series, it's explained that the word is nothing more than a release for the will, hence the magic is the Will and the Word.
In the Elenium/Tamuli, the magic turns out to be nothing more than a prayer to the gods for assistance, which takes the form of magic. The Church Knights, given special dispensation to take on non-church tutors in mystical arts are the primary users. This leads to the hilarious revelation later that they probably didn't have to go outside their own religion.
In Christopher Paolini's Inheritance Cycle the elven language is the Language of Magic and spells are more or less words of power taken from it. Want a big fire or an explosive arrow? Just yell "Brisingr!" and you're all done. (So long as you've got access to magic, that is. It won't do you much good otherwise.)
Then, in the final book, Galbatorix learns the name of the ancient language, giving him complete control over all magic. Good thing he uses it stupidly.
In Snow Crash by Neal Stephenson, words literally can break bones - the human body and brain can be traumatized by carefully selected words. Of course, it's not that simple - not just any words can kill, but only those linked to "deep connections" in the brain. The language Sumerian works on anyone; binary also works on computer hackers.
Jadis (the future White Witch) in The Magicians Nephew knows the Deplorable Word, the word which ends all life in a world - and spoke it to end the world of Charn where she ruled. Luckily for us, it doesn't work in this world.
Numair in The Immortals knows and uses words of power: he once used one to turn an enemy mage into an apple tree. It is not quite a Dangerous Forbidden Technique but very much discouraged because it can create unintended havoc—anything performed by a word of power has an opposite effect somewhere else in the world. (Pierce did eventually write a short story about the tree who became a man. He had a lot of trouble adapting.) Good thing he's with the good guys.
The magic words of the Harry Potter universe probably fit here, although the words alone aren't enough; you've got to be a wizard with a wand and you've got to say them just right and in some cases you've got to have the right willpower behind it. It's not otherwise explained much or known if they're part of a Language of Magic but most of them are pseudo-Latin.
Magic can be performed without saying the words but just thinking them, which Snape tried to teach in Half-Blood Prince. It's hard though, so many wizards still use incantations when outside of areas in which a non-verbal spell is required, like a battle.
It's even possible to cast spells Wandless, but for an adult wizard and barring instinctive, unconscious magic, it is implied to be VERY difficult to do.
Avada Kedavra, the Killing Curse, was based on a twisted interpretation of Abracadabra, as mentioned below. Some translations simply use Abracadabra, in cultures probably where the words have not come to be known as a cheesy magician's catch phrase.
More specifically, the Taboo on Voldemort's name goes hand in hand with this trope. A single utterance of a man's name causes the trio to be whisked away perilously to Malfoy Manor and its impending danger.
Brenwyr is a "maledict": if she curses something or someone, the curse becomes real. (At one point, she strikes a table and says "Rot you!". The table promptly crumbles to dust.) She also totters on the edge of being Ax-Crazy.
The Book Bound in Pale Leather contains Master Runes, which work independently of who reads them. Just copying them is dangerous and will drive you crazy.
In the Dresden Files wizards choose either nonsense words or a dead language as a link to their power, and those become their spells.
They COULD pick words in their own language, but this is dangerous, since using a language you can't speak creates a mental barrier that helps protect the wizard from energy backlash.
It's also possible to cast spells without using words at all, and simply shaping the magic with your mind, but it is also incredibly painful. Harry equates it with all his bones being lit on fire at once.
The UnWords of Enuncia in Ravenor probably count. The head of the Secretists uses several to very brutally murder a number of people including (if memory serves) the head of Special Crimes; and Patience Kys uses one to escape while being held prisoner by the Secretists. Bonus points for having the UnWords actually hurt the people saying them as well.
Miranda Windwood Rose, from the short story of the same name by Janni Lee Simner, is a magic name, letting the owner hear and see magic. This leads to the main character being an outcast.
In the Myst novels, the backstory of the "magical books" is fleshed out; we learn about "mighty words," which if used in the proper context (that is, with the right ink and on the right paper) can modify the linked world. And Earth was originally reached by the D'ni through such a Book.
Though the linking process works more akin to a magical search engine, the book seeking out the world that best fits the description given, the words used can also change a world once the link is made, and are described in terms of this trope. In The Book of Atrus, Anna explains about 'levels' of words, the simplest being a description of a thing, the next being a modifier of such a description, i.e. a meta-word. She never says what the third level is, but it's implied to be the performative word, one which alters what it describes.
in The Book of All Hours by Hal Duncan - the Cant, the metaphysical language of the Vellum. Humans transform into Unkin when an event in their lives causes them to hear the Cant from underneath reality, echoing from the Vellum. Unkin can then use it to reshape reality, warp and change spacetime itself as well as the Vellum.
In The Lord of the Rings legendarium, where the world was essentially sung into existence, words and song have great power. Many of the most significant magical acts in the series are not of the fire and brimstone variety, but rather acts of word or song that influence the nature of their surroundings in the speaker's favour. Names also have a power; names such as Elbereth and Eärendil are used to repel creatures of the Shadow, and Treebeard warns Merry and Pippin against giving out their right names lightly.
A form of this in Tales of Kolmar. Servants of the Goddess Shia in times of great peril can be blessed by Her for an instant, and in that instant She speaks through them, using words they don't understand and don't need to have ever heard before. Nobody knows what they mean, but nothing can stand against them - and when they're spoken in this way, it's said that someone close to the Servant, someone they value dearly, dies within seven days. However, someone can know these words and even say them without either effect. The Goddess speaking these words is the big thing here, not the words themselves.
Casey Fry's Death Speaker has a type of creature called a DeathSpeaker who kills whoever hears them utter a single sound. Made worse that these creatures are just humans who are mute until they can suddenly speak at ten-years-old, and they have no control over their power.
The overlord of the Redeemers in Star Trek: New Frontier knew words that could do things from inflicting severe pain, to forcing a person to reveal everything they know (which was actually used, and it wasn't a pretty sight). Their one weakness is that they can be blocked by Starfleet Universal Translators because they're from a language the Translators don't recognize.
Live Action TV
Doctor Who, "The Shakespeare Code": The Carrionites use words to shape reality; the right words said in the right way at the right time have dramatic effects. Unfortunately for them it works both ways and The Doctor's enlisted the best wordsmith around: Shakespeare. They get an assist from J. K. Rowling too, via Martha: turns out that Expelliarmus! just happens to fit the end of his incantation to banish them nicely.
He also ends Harriet Jones's career with six words. "Don't you think she looks tired?"
An episode of Samurai Sentai Shinkenger/Power Rangers Samurai has a monster that can read a person's mind, find the most derogatory and damaging insult that person has ever been called, and repeat it to them, converting the emotional pain they suffer from the insult into physical pain. He's only defeated when it's revealed one of our heroes has gotten so used to being insulted in her life that the monster's power can't affect her. Interestingly, the monster is based on a Japanese Obake that, itself, suffers from Words Can Break My Bones...in reverse: it "feeds" off of a person's inner thoughts, repeating them in the open when they latch onto someone, and only by emptying your mind of all thoughts can you drive away (or even kill) the creature.
Of course, the Shinkengers themselves indulge in this trope with their "Mojikara", or "word magic"; essentially, they use traditional Japanese calligraphy (written in the correct brushstroke) to create or invoke certain things, such as summoning a horse by writing out the kanji for "horse". (The Samurai Rangers do the same, but their "Samurai Symbols of Power" were never acknowledged as an actual written language.) The team's Sixth Ranger, unfortunately, sucks at penmanship, so he does his mojikara through cell phone text messages.
A variation on Babylon 5: Telepaths, in addition to scanning minds and planting thoughts or visions, can also effectively hit the target's "pain button", making every nerve in their body burst with blinding pain for a few moments. This is typically accompanied by them simply glaring at the other person and hissing "Pain!" It is only allowed to be used in self defense, and it is only used when more effective means, such as guns, are unavailable.
Technomages claim they can also make anyone do certain things just by speaking certain words. The trilogy of novels about them, though, implies that it's all bullshit.
In Jewish lore there are ramifications for speaking the True Name of God or erasing the written version. There is also the folklore of the Golem of Prague where the word emet was used to bring life to a piece of earth.
The Bible: The Book of John starts out with "In the beginning was the Word..." This is the authors way of stressing the primacy of Jesus, as the Word of God incarnate.
In Greek it's "Ἐν ἀρχῇ ἦν ὁ λόγος." Granted, "word" is one possible translation of "λόγος", but so are "argument" and "study" (hence any English word that ends in "-logy") and probably a few other meanings besides.
The medieval theologian Erasmus translated it as "sermon," which may be seen as a sign of how important Scholastic works on religion were getting to be at the time.
And then there's the parodies. In the beginning was the Word...
The most famous examples are the "Power Word" spells, including the ones for Blind, Kill and Stun. Power Word: Kill is as bad as it sounds: target within range with certain amount of HP/hit dice drops dead, no saving throw.
Similar and related are certain rune spells such as Symbol of Death - yep, it's at least as nasty if you step on it.
The dark speech, as introduced in the Book of Vile Darkness, is capable of damaging solid objects and driving people insane, as well as forming a component of seriously nasty (by D&D standards) magic.
The Various Splatbooks feature tons of variants on this trope. Warlocks can shatter objects, disable flight, and turn people into frogs just by saying single words of the black speech. The Dracolexi Prestige Class can light people on fire just by speaking Draconic. But the one class that takes this trope to the extreme is the Truenamer from Tome Of Magic, who can temporarily reprogram the universe. Theoretically.
Fourth Edition introduced the bard power "Vicious Mockery", which causes psychic damage and is described in fluff as a string of vulgarities and insults, allows a player to literally talk someone to death.
Every spell with a verbal component fits the trope. Though most of the damaging ones also require a physical component, there are few non-attack, purely spoken spells that can be cleverly used to break bones.
Tenebrous's/Orcus's last word was so powerful that the utterance could instantly slay even deities. In fact, it was so powerful that unless you were a true god, usage of this word would eventually burn you out. After Tenebrous's shenanigans, a cabal of greater deities greatly lessened the power of the word.
3E and 3.5E have a whole family of spells that do this to creatures of the opposite alignment. A cleric who casts Holy Word (seen in action in The Order of the Stick#859) causes any evil creature within 40 feet to suffer an escalating series of effects depending on the difference between the caster level and the victim's hit dice. If the two values match, the subject is merely deafened, whereas if the difference is ten or more, the subject is deafened, blinded, paralyzed, and killed instantly. Also, non-good extraplanar creatures are immediately banished. Holy Word's counterparts for the other alignments are Blasphemy (affects good subjects), Dictum (affects chaotic subjects), and Word of Chaos (affects lawful subjects).
The Words of Power from GURPS: Thaumatology are described as "the ultimate symbols of which all others are merely shadows". Despite their enormous power the Words are cheap (in game terms) to learn because they're impossible to control. "Fire" might do anything from inspire poetry to create a massive explosion or even do both at once.
The rules also note that a word of power has a reasonable chance of doing the speaker a serious mischief on the way out.
Exalted charms can cause this in many different ways. A tongue-lashing can cause very real damage and in the case of some specific charms and combos, a person can be harmed or killed by just reading a letter.
Hollow Earth Expedition. A character who knows the Atlantean language and has the talent Atlantean Power Words can order opponents by using one word commands in Atlantean. If he has the Atlantean Commands talent as well he can issue complex multi-word commands.
Similar to the example from Six Six Six Satan, in the RPG Rudra No Hihou, magic is based on entered words... and possible effects for entries that don't have a specific precoded effect involve the word simply attacking enemies, such as flying at them from offscreen or being dropped on them by an eagle.
Towards the end of Alan Wake you go into a weird abstract world with a bunch of typewritten words that hover in mid-air. Shining your light on them cause them to manifest the things they represent. For instance, "Exit" will create a way out of the area, or "Red Box" will spawn a supply chest. In the DLC they introduce considerably more dangerous ones, like "Taken", "Birds", and "BOOM!"
The scrolls in the Diablo series work this way, with the written words becoming the spell as they're spoken (and consequently, disappearing). The magic books from the first installment may be similar, as they too disappear when used.
In Baldur's Gate all casters say three short words in latin before any spell depending on the school, which read less like magical gibberish and more like an invocation.
Abjuration: "Manus, Potentis, Paro" = "A hand, powerful, I prepare"
Alteration: "Praeses, Alia, Fero" = "Protecting, another, I bring this forth"
Conjuration: "Facio, Voco, Ferre" = "This I do, I call, to bring you forth"
Divination: "Scio, Didici, Pecto" = "I know, for I have studied, with my mind"
Enchantment: "Cupio, Virtus, Licet" = "I want, excellence, allowed to me"
Evocation: "Incertus, Pulcher, Imperio" = "Uncertain, beautiful things, I command"
Illusion: "Veritas, Credo, Oculos" = "The truth, I believe, with my eyes"
Necromancy: "Vita, Mortis, Careo" = "Life, and death, I am without"
In The Elder Scrolls V: Skyrim Many Thu'um shouts are capable of harming foes, with things like sending them flying through the air, freezing them with cold, or summoning a storm to fry them with lightning. The Greybeards, an order of monks who have mastered this ability, have only one member skilled enough to speak in a normal tone of voice with enough restraint to avoid accidentally killing people by uttering a single word.
In Ultimate Marvel vs. Capcom 3Phoenix Wright can use his iconic "Hold it!" and "Objection!" as attacks that can stun opponents. His level 3 hyper combo consists in him accusing the opponent of being "the one who actually committed the crime", finalizing with a "Take That!" Balloon. This happens to be the second most damaging move in the whole game, only losing out to Vergil's Level 3.
In Lollipop Chainsaw, Zed the Punk Zombie can attack by weaponizing profanities. He does this by blasting you with giant versions of the words he shouts out, like COCKSUCKER! or PISS OFF!, to demonstrate a few.
In Manhunt 2, Daniel Lamb's mind can be destroyed if Dr. Pickman completes the following quote within earshot: "What seest thou else in the dark backward and abysm of time?"
In Planescape: Torment, the museum/art gallery has a "statue" which is actually a wizard who was petrified just before he could start cursing some enemy. A player can potentially restore him, whereupon he completes his tirade. The resultant profanities are so utterly vile they kill you instantly. Doing this is one of the ways the player can enhance Morte's Taunt special attack.
At the beginning of Mario & Luigi: Superstar Saga, Cackletta infects Peach with a bizarre condition where anything she says will manifest as swear-like symbols that fall down from her speech bubble and explode upon hitting the floor. Cackletta describes it as "an explosive vocabulary."
The Parodius series has a megaphone powerup that spouts random silly phrases which, upon contact to enemies, does tremendous damage.
The Correspondence in Fallen London is a writing system which has this effect. Attempts to study it tend to set things on fire, ranging from the material it's written on to would-be cryptophilologists themselves. Writing Correspondence symbols in lead seems to mitigate the issue, but only to an extent. It's also known to make the reader's eyes bleed.
Torg of Sluggy Freelance gives Zoë a fancy necklace he found in an Egyptian pyramid that turns out to carry a curse that causes its wearer to transform into a camel when someone in earshot says the word "shupid". Fortunately, the effect can be reversed by speaking another magic word, "kwi". Unfortunately, the necklace, upon being put on, turns into a tattoo on the wearers chest, and cannot be removed.
In Rice Boy, the titular character learns to speak a word in the Thrill language. It allows him to cut anything in half.
Gordon Frohman of Concerned only survived falling down from the Citadel because he had Buddha mode on (apparently he could use Half-Life 2 cheats by saying them out loud). It didn't prevent him from getting fatal injuries, only from succumbing to them. Of course, saying "buddha" again in such a situation is ill-advised. He learned this the hard way...
The word path in Juathuur is one of the three types of magic.
Played with and subverted in The Grim Adventures of Billy & Mandy. While no magic is involved, Billy does tell Spurg the whole "sticks and stones" thing. Then Spurg shows Billy that he indeed has with him sticks and stones.
Raven's magical exclamation on Teen Titans: AZARATH METRION ZINTHOS!!
However, its shown that its not an intrinsic property of the words that have power, but rather that they mean something important to Raven herself.
In the Bugs Bunny cartoon "Transylvania 6-5000", the vampire Count Bloodcount can turn himself into a bat by saying "Abracadabra", and turn himself back by saying "Hocus Pocus". Bugs keeps saying the words at random, even making up a song about them, causing the Count to turn into a bat and back at the most inopportune times. Bugs then starts getting creative.
Abraca-pocus. (Count turns into vampire with a bat's head) Pocus-cadabra. (Count turns into bat with vampire's head) Newport News. (Count turns into Witch Hazel) I can do better than that. Walla-Walla Washington. (Count turns into two-headed vulture.)
Topping it off, Bugs himself grows bat wings just by singing "Abraca-pocus".
"Abracadabra" came to us from as far back as the 2nd century CE, believed to be Aramaic (a Semitic language related to Hebrew) in origin, or maybe Arabic, used as a charm against misfortune. In Arabic the meaning was "let the thing be destroyed," while the thing being destroyed was typically illness, or possibly "let it be as I have said." It might also have come from Aramaic first, where abra (אברא) means "to create" and cadabra (כדברא) which means "as I say."