Dementor

"Dementors are among the foulest creatures that walk this earth. They infest the darkest, filthiest places, they glory in decay and despair, they drain peace, hope, and happiness out of the air around them... Get too near a Dementor and every good feeling, every happy memory will be sucked out of you. If it can, the Dementor will feed on you long enough to reduce you to something like itself... soulless and evil. You will be left with nothing but the worst experiences of your life."

- Description of Dementors

A Dementor is a gliding, wraith-like dark creature (considered one of the foulest to inhabit the world) employed by the British Ministry of Magic as the guard of Azkaban Prison. The Dementors feed upon human happiness, and thus cause depression and despair to anyone near them. They can also consume a person's soul, leaving their victims in a permanent, and thus are often referred to as "soul-sucking fiends". They are known to leave a person as an 'empty-shell'.

The Dementors of Azkaban were under the employ of the Ministry until mid-1996, when Lord Voldemort was sighted in the Ministry, and their defection to the Dark Lord's cause became undeniable. The Dementors supposedly led the Death Eaters and Voldemort into the Ministry of Magic. After the end of the Second Wizarding War in 1998, the Ministry was reformed, and Minister for Magic Kingsley Shacklebolt ensured that they were not used by the government again, presumably because of their actions in support of Voldemort and due to ethical reforms in the Ministry and Wizarding society at large.

There are certain defences one can use against Dementors, specifically the Patronus Charm. Dementors hold no true loyalty, except to whomever can provide them with the most people to feed off. They cannot be destroyed, though their numbers can be limited if the conditions in which they multiply are reduced, implying that they do die off eventually.

Early history
"Those who entered to investigate refused afterwards to talk of what they had found inside, but the least frightening part of it was that the place was infested with dementors."

- J. K. Rowling on the early history of Azkaban

The history of Dementors in relation to Wizarding society in Britain are inextricably tied up with one location: Azkaban. The island in the North Sea on which the wizard prison is built has never appeared on any map, wizard or Muggle. Perhaps its first resident, or even creator, Ekrizdis, practised the worst kinds of Dark magic and constructed a fortress on the island, luring Muggle sailors there to torture and murder them. After his death, the various concealment charms placed on the island faded, and the Ministry became aware of the mysterious site's existence.



Those who entered the deserted fortress to investigate discovered, among other horrors, an infestation of Dementors. Fearing the reprisal of these dark entities should anyone try to evict them, the Ministry decided to let the sizeable colony remain, unmolested and unchecked.

When Damocles Rowle was elected Minister for Magic in 1718, he insisted on utilising Azkaban's dark pedigree, seeing the Dementors as a potential asset: putting them to work as guards would save expense, time, and lives. This plan was eventually put into motion and, despite protests, Azkaban remained the prison of the wizarding world right up until the Second Wizarding War, mostly because of its near-zero breakout rate. From that point on, the Dementors served the Ministry of Magic as the guards of Azkaban, as the arrangement allowed them to feed on the emotions of the prisoners within its walls. Somewhere between 1733 and 1747, Minister Eldritch Diggory visited Azkaban, and was horrified at the sheer despair and insanity that the Dementors induced within the prisoners. He formed a committee to find alternative solutions, the least of which was to remove the Dementors, which met opposition from those who feared a mainland invasion by the dark creatures if they were deprived of their food source. Diggory died of Dragon Pox while in office, and thus the campaign to find an alternative to Azkaban's Dementors stalled.

Although many in the wizarding world felt they could sleep easy at night in the knowledge that Dementors guarded Azkaban, making it virtually impossible for dangerous criminals to escape, some believed the Dementors to be untrustworthy, fearing their potential change in allegiances should a dark wizard arise who might offer them more promising compensation than the Ministry. Albus Dumbledore, in particular, thought it was a mistake for the Ministry to ever ally with such creatures, though Alastor Moody thought violent criminals such as Death Eaters deserved such treatment.

1993-1994
"When they get near me — I can hear Voldemort murdering my mum."

- Harry Potter on the Dementors' effect on him



During the 1993-1994 school year, Dementors were sent to guard Hogwarts School of Witchcraft and Wizardry against "mass murderer" Sirius Black, who had recently escaped from Azkaban in 1993. On the Hogwarts Express, Harry Potter had his first first encounter with a Dementor. Whenever brought into close proximity with one, Harry was forced to relive his worst memory: hearing the last moments of his parents' lives before they were murdered by Lord Voldemort. The first of these encounters was on the Hogwarts Express, during which he was protected by the new Defence Against the Dark Arts professor, Remus Lupin. While the Dementors were at Hogwarts, Headmaster Albus Dumbledore refused to let them enter the School Grounds, but was unable to prevent their presence entirely, and so warned his students to give the Dementors no reason to harm them. So dangerous did Dumbledore consider them to be that, even when Sirius Black was found to have entered the school, he refused to let them search or enter the castle.



Harry endured a second encounter with a group of Dementors during a Quidditch match, causing him to lose consciousness and suffer a fall from his broom. He was that time rescued by Dumbledore, who slowed Harry's fall and then drove the Dementors away with a Patronus. They seemed to be particularly attracted to Harry due to his miserable childhood and plentiful bad memories. Professor Lupin later claimed that the atmosphere of excitement during a Quidditch Match would be like a feast to the Dementors, which they were unable to resist.

To overcome the Dementors, Harry asked Lupin for assistance. Lupin began teaching Harry the Patronus Charm, using a boggart, which transformed into a Dementor in front of Harry. During the next Quidditch match Harry competed in, four Slytherins, Draco Malfoy, Vincent Crabbe, Gregory Goyle, and Marcus Flint, disguised themselves as Dementors to distract Harry. Although not yet capable of producing a fully formed patronus, Harry was able to perform the spell well enough to thwart their attempts and won the match, after which Professor Minerva McGonagall sentenced the offending students to detention and deducted fifty House Points from Slytherin.



Harry's next encounter with the Dementors came when he, Hermione, and Sirius were attacked by a group of them in the Forbidden Forest; the three were saved by the intervention of a powerful and fully formed Patronus before the Dementors were able to take their souls via the Dementor's Kiss (defined below). Though initially believed (by Harry) to be the Patronus of his deceased father, this Patronus had in fact been conjured by Harry himself, who had travelled back in time with Hermione Granger using her Time-Turner (this technically counts as both Harry's third and fourth encounter with the Dementors, since, due to his time travelling, he experienced this same encounter twice). Harry's Patronus took the form of a stag, which was both the form his father's Patronus took and the form his father took as an Animagus. Because the Dementors tried to Kiss Harry during this encounter in the Forest, it was enough to convince the Minister for Magic Cornelius Fudge to have the Dementors removed from Hogwarts at the end of the school year. Dumbledore seemed very happy about this.

1995-1996
"The Dementors will join us, they are our natural allies...."

- Lord Voldemort talking to his Death Eaters

Harry met an apparent Dementor in the Triwizard Tournament; thinking that it was a real Dementor he conjured the Patronus Charm, and soon the Dementor stumbled and then Harry knew it was a boggart and soon cried 'Ridikkulus'.



Harry's fifth encounter was in an alley near his home on Privet Drive, when he and his cousin, Dudley Dursley, were ambushed by two Dementors sent secretly and illegally by Dolores Umbridge. He successfully used the Patronus Charm and was subsequently rescued by a Squib named Arabella Figg. Harry was put on trial for his use of underage magic, but ultimately was not punished, as it was recognised as having been self-defence. Nearly a year later Umbridge admitted the plan to attack and undermine Harry using the Dementors.

By July 1996, all of the Dementors of Azkaban collectively rebelled against their employers to join Lord Voldemort, who offered them more victims and free rein across the country. This aided the 1996 and 1997 escapes of Death Eaters from Azkaban. By mid-1996, the Dementors who had joined Voldemort were multiplying in such quantities as to generate an 'unseasonal' July mist, noticeable to both the Muggle and wizarding worlds alike. Cornelius Fudge also admitted they were factors in the British Prime Minister's recent decline in terms of public approval, as they were making people less happy in general.

1997-1998
"The air around them had frozen: Harry's breath caught and solidified in his chest. Shapes moved out in the darkness, swirling figures of concentrated blackness, moving in a great wave towards the castles, their faces hooded and their breath rattling...."

- Dementors join the Battle of Hogwarts



During the 1997 infiltration of the Ministry of Magic, while Harry Potter was disguised as Albert Runcorn, he encountered the Dementors in the Muggle-Born Registration Commission court room, where they were used to take away convicted Muggle-borns after interrogation and to terrorise them during interrogation. Dolores Umbridge protected herself and the other questioners with a cat Patronus, which dissipated when Harry stunned her. Harry and Hermione then performed the charm to save the Muggle-borns who had yet to be interrogated from the Dementors.



After Apparating to Hogsmeade, Harry, Ron, and Hermione set off a Caterwauling Charm and hid under Harry's Invisibility Cloak. Unable to find them the Death Eaters dispatched Dementors to attack the trio, as Dementors sensed the presents of others and did not rely on sight. Harry was forced to cast his Patronus to protect the trio from being kissed. They could not Disapparate due to an Anti-Disapparition Jinx placed on the village, and were stuck. Harry drove away the Dementors, but almost gave the three away, as his Patrouns was very distinctive, Aberforth Dumbledore saved them and passed off Harry's stag as his own goat Patronus and ushered the trio into his pub.



Later, during the Battle of Hogwarts, the Dementors fought on the side of Lord Voldemort and the Death Eaters. Harry Potter, Hermione Granger, and Ron Weasley were attacked by large numbers of Dementors, and due to the horrific events they had experienced and witnessed, including the recent death of Fred Weasley, they all had difficulty summoning their Patronuses. In fact, Harry welcomed the fate that came with a Dementor's kiss, but Seamus Finnigan, Luna Lovegood, and Ernie Macmillan attacked the Dementors with their own Patronuses holding them at bay and encouraged Harry to do the same, allowing him to finally summon his Patronus, which caused the Dementors to scatter. Later, Harry encountered more Dementors in the Forbidden Forest, but the presence of James, Lily, Sirius and Remus, summoned through the Resurrection Stone, shielded him from them.

Post 1998
After the Second Wizarding War, the Ministry of Magic became headed by former-Auror and Order of the Phoenix member Kingsley Shacklebolt. Due to their actions during the war (allowing Death Eaters to escape back to Voldemort and joining forces with him themselves), Shacklebolt disbanded the Dementors as guards of the wizard prison. It is unknown where they went or what they did without their only known application. After the Dementors were removed from the prison, Aurors were placed in the prison as guards.

Appearances
Dementors have a humanoid shape, approximately three metres, or 10 feet high, and are covered in dark hooded cloaks of long ripped black cloth, making them closely resemble wraiths. Its body is greyed and decayed looking, like a decomposing corpse, and its breath sounds rattling, like it is trying to "suck more than air" out of a room. Its hands are "glistening, greyish, slimy-looking, and scabbed". They seem to exude cold.



A Dementor's face has empty eye sockets, covered with scabbed skin. There is a gaping large hole where the mouth should be, which is used for sucking the soul out of the victim in a process called the Dementor's Kiss, leaving victims in a state generally considered worse than death. The Dementor pulls back its hood and sucks out its victim's soul, leaving the person an empty shell, alive but completely, irretrievably 'gone'. They are described as being able to glide over the ground only, and in any case, they cannot pass through solid obstacles.

Dementors are also known to be blind, as they do not have eyes. However, they can sense whether a presence is near them or not, by sensing the victim's emotions.

Nature and behaviour
"He felt the unnatural cold begin to steal over the street. Light was sucked from the environment right up to the stars, which vanished... The cold was biting deeper and deeper into Harry's flesh... Then, around the corner, gliding noiselessly, came Dementors, ten or more of them, visible because they were of a denser darkness than their surroundings, with their black cloaks and their scabbed and rotting hands. Could they sense fear in the vicinity? Harry was sure of it: They seemed to be coming more quickly now, taking those dragging, rattling breaths he detested, tasting despair on the air, closing in —"

- Description of Dementors as they close in



Dementors seem to suck all the light and happiness from the air as they draw long rattling breaths, and cause darkness to close in everywhere and the victim to feel incredibly cold. They can glide toward a victim without sound, and they are sentient enough to taste and sense fear, being drawn to it and the promise of positive memories that it can feed off of. They are also intelligent enough to be greedy: they obeyed the Ministry of Magic for years because, in guarding Azkaban, they were provided with sustenance of any remaining hope or happiness in the prisoners. They can understand and follow at least simple instructions, which allowed a Dementor to act as a bodyguard to Minister for Magic Cornelius Fudge in 1995, and for them to escort prisoners in and out of the Muggle-Born Registration Commission courtroom in 1997.

They could communicate what they had heard Sirius Black saying in his sleep to the Ministry in 1993, implying that they can speak or otherwise communicate with wizards. Albus Dumbledore also describes Dementors as vicious creatures and that they won't ever distinguish between those they are hunting and those that are in their way. He also informs the students to give Dementors no reason to harm them, saying that forgiveness is not in a Dementor's nature.

Outside of Azkaban, Dementors appear to hunt for prey in groups of variable size, from as small as two to as large as greater than twenty. They appear to attack by first surrounding their targets, cutting off any escape, then descending upon them all at once to feed.

Abilities
"They don't need walls and water to keep the prisoners in, not when they're trapped inside their own heads, incapable of a single cheerful thought. Most go mad within weeks."

- Remus Lupin on Azkaban prisoners' long-term exposure to Dementors

Being blind, Dementors sense and feed on the positive emotions of human beings in order to survive, forcing their victims to relive their worst memories over and over again. The very presence of a Dementor can make the victim's surrounding atmosphere grow cold and dark, and as the number of Dementors increase, so do the effects. Those that are kept in the company of a Dementor for too long tend to become depressed, and are often driven insane, which was the main source of Azkaban's well-deserved horrible reputation when they still guarded its prisoners. After spending only a few months there, Rubeus Hagrid claims he wished he would die in his sleep.



Dementors rely fully on their ability to sense emotion and physical and/or mental health to track the movements of the prisoners in their care, and are generally unable to distinguish one person from another if both are in similar physical or mental condition. They were unable to identify Mrs Crouch being sneaked into Azkaban disguised as Bartemius Crouch Jr using Polyjuice Potion, or Barty Crouch Jr being sneaked out disguised as his mother, since both were ill nearly to the point of death, as divulged by Bartemius Crouch Jr under the influence of Veritaserum in 1995 (though it may be that they simply did not care who they were sucking happiness from so long as they were "fed"). They can also not distinguish between humans and animals very easily; Sirius Black, an Animagus, escaped from Azkaban in his dog form. When he became his dog form during imprisonment, the Dementors thought he was losing his mind as his emotions were less human in his animagus form.

Although Muggles cannot see Dementors, they are affected in a way similar to wizards and witches, becoming depressed when near them. While at least one Squib, Arabella Figg, has claimed to see a Dementor, the truth is that Squibs cannot see them, but have enough magical knowledge to identify their effects.

After Bartemius Crouch Jr's mother died in Azkaban, Dementors buried her body, which shows that Dementors are capable of physical labour, such as grave-digging. Also, Sirius escaped when the Dementors came to give food, another sort of labour.

It is stated by Remus Lupin that, if a wizard remains in close contact with Dementors for an extended period of time, a Dementor can drain a wizard of his powers. This fact is not expounded upon, so the truth to this statement is unknown. If this is the case, however, it would make Dementors the only known being to permanently render a wizard without magic. Lupin might also mean this metaphorically, as severe depression, which is caused by prolonged contact with Dementors, can be really detrimental to a wizard's ability to cast spells.

Dementor's Kiss
"There's no chance at all of recovery. You'll just... exist. As an empty shell. And your soul is gone forever... lost."

- Remus Lupin regarding the kiss



In addition to feeding on positive emotions, Dementors can perform their last and most dangerous ability: the Dementor's Kiss, in which a Dementor latches its mouth onto a victim's and sucks out the person's soul. The victim is left as an empty shell, incapable of thought and with no possibility of recovery. It is believed that existing after a Dementor's Kiss is worse than death: as a person's soul is their true self, to be 'kissed' by a Dementor is to cease to exist, and yet also remain. The Ministry of Magic occasionally allowed this as a punishment, before Kingsley Shacklebolt became Minister for Magic. It is unknown what effect a Dementor's Kiss would have on a person who had split his or her soul through use of a Horcrux. It is also possible that the soul is trapped inside the Dementor, thus the victim in unable to pass on. This is probably what "worse than death" is.

The only known named victim of the Kiss is Barty Crouch Jr. From 1994 to 1995 Crouch had been using polyjuice potion to pose as Alastor Moody, and had been teaching at Hogwarts in his stead; he was detained at the castle, awaiting trial, after his ploy was discovered, and it emerged that he had been working in secret for Voldemort. He was subjected to the punishment by a Dementor accompanying Cornelius Fudge as bodyguard. The unfortunate consequence of this act was that it rendered Crouch unable to testify about his master's return, allowing Voldemort almost a full year to gather strength while the Ministry continued in its denial.

Patronus Charm
"A Patronus is a kind of positive force, and for the wizard who can conjure one, it works something like a shield, with the Dementor feeding on it, rather than him."

- Remus Lupin regarding what a Patronus is



No one has ever demonstrated the ability to kill a Dementor, by Avada Kedavra or otherwise, implying that they can not be killed through physical means, but can only be driven away or temporarily kept at bay. One of the few ways to shield oneself from Dementors is by the very difficult Patronus Charm. The charm summons a Patronus, a magical manifestation of good will and happiness, providing varied levels of protection against the Dementors' influence, based on the caster's strength as a wizard. With sufficient ability, a single wizard can hold off dozens, if not hundreds, of Dementors with a single corporeal Patronus, as Harry Potter demonstrated during his third year at Hogwarts when he drove off a horde of Dementors seeking to consume Hermione Granger, Sirius Black, and Harry's past selves.

As the Patronus is not alive, the Dementor cannot feed on it. Only when summoned by an experienced caster will the Patronus take the form of an animal significant in some way to the individual. While the lower level Patronus is more amorphous and ephemeral, corporeal Patronuses chase down Dementors and force them to flee the vicinity. An incorporeal Patronus only slows a Dementor down, as if the creature is walking through quicksand, and tends not to last long.

Other
Since Dementors can not properly sense the less complex thoughts and emotions of a person when he or she takes on an Animagus form, doing so allowed some, such as Sirius Black, to temporarily avoid feeling the effects of the Dementors' presence. When they sensed the less-than-human thoughts of his Animagus form, the Dementors simply thought Sirius was losing his mind.

The effects of a Dementor's happiness-draining powers can also be resisted if one focuses not on happy thoughts, but on obsessions, or other things that give one strength without exactly making one feel better. For example, Sirius managed to avoid going mad in the Dementors' custody and eventually plan an escape by focusing on the fact that he was innocent and didn't belong in Azkaban, and later that Peter Pettigrew was at Hogwarts and that Harry was in danger.

Though clearly not a common method of repelling Dementors, the enigmatic form people take after being brought back by the Resurrection Stone appears to function much like a Patronus, as the 'resurrected' forms of Sirius Black, Remus Lupin, and James and Lily Potter were able to shield Harry Potter from the Dementors that Voldemort had stationed in the Forbidden Forest in 1998.

There may be another, more common way of repelling a Dementor, aside from the Patronus Charm, as Harry Potter disagreed with Professor Snape on the best method for confronting one when it was the subject of a report in his sixth year. This implies that there are, indeed, other methods.

The mood-enhancing properties of chocolate are well known in both the Muggle and wizard worlds. Chocolate is the perfect antidote for anyone who has been overcome in the presence of Dementors, which suck hope and happiness out of their surroundings. Chocolate can only be a short-term remedy, however. Finding ways to fight off Dementors — or depression — are essential if one is to become permanently happier. Excessive chocolate consumption cannot benefit either Muggle or wizard.

Dark Wizards cannot commonly produce Patronuses. However, they do not need to do so in the first place, as they are like-minded in evil. Voldemort even states that they are natural allies. This does not however prevent Dementors from imprisoning dark wizards in Azkaban.

Etymology
The English word dementor is used generically to refer to any evil or fearsome creature. The word ultimately derives from the Latin dēmens, meaning "insane".

Behind the scenes

 * J. K. Rowling has revealed that the inspiration for Dementors came from her bout with severe depression before her phenomenal success. She described the feeling as an "absence of being able to envisage that you will ever be cheerful again. The absence of hope. That very deadened feeling, which is so very different from feeling sad."
 * In an attempt to sabotage Harry during a Quidditch match in 1994, Draco Malfoy, Vincent Crabbe, Gregory Goyle, and Marcus Flint dressed up as Dementors to scare him. Malfoy was standing on Goyle's shoulders. Considering how tall Dementors are (they are described in Prisoner of Azkaban as reaching from the floor to the ceiling on the Hogwarts Express), the foursome appear to account for two Dementors, when just a few pages earlier, Harry saw three Dementors. (Although Marcus Flint, as an older student — in his seventh year — may have been tall enough to pass as a Dementor without someone on his shoulders.) However, their attempt failed when Harry cast a Patronus Charm at them.
 * Animatronic Dementors appear in at, chasing the riders' flying bench through the Chamber of Secrets and around the skeleton of the Basilisk. The Dark Mark appears along with them, suggesting that a Death Eater summoned them to Hogwarts.
 * Dementors are often compared to the Nazgûl from ', as well as the Spectres from '. They can also be compared to the Ra'zac of The Inheritance Cycle in that the foul breath of the Ra'zac engenders terror and lethargy in humans, though the Ra'zac cannot be repelled by a simple charm, nor are they are amortal spirits that cannot be truly destroyed.
 * According to W.O.M.B.A.T., Dementors may be unknown in tropical regions.
 * In, a large Dementor serves as the final boss of Year 3.
 * J.K. Rowling has said that Dementors don't breed, but grow like fungi where there is decay; and are functionally immortal in terms of age.
 * The Dementors' appearances (tall corpse-like beings wearing tattered black cloaks) is very similar to popular depictions of the Grim Reaper. Because of this, some readers assumed Dementors were incarnations of death rather than depression; the concept was very notably used in Harry Potter and the Methods of Rationality.
 * In, Aberforth repels the attacking Dementors in the Battle of Hogwarts with a wave-like Patronus, similar to the one cast by Harry in the film version of Prisoner of Azkaban.
 * In Harry Potter and the Order of the Phoenix, a Dementor that was pining Harry Potter against a wall by the neck while feeding on his emotions and soul was briefly repelled when Harry touched his wand to the Dementor causing red sparks to fly off and to make the Dementor release him, similar to the Revulsion Jinx, implying that the spell could work on Dementors.
 * Dementors and the Dementor's Kiss exhibit interesting parallels to Lord Voldemort and the spell that creates a Horcrux:
 * The Dementor's Kiss sucks out a victim's soul, while the Horcrux spell allows part of the caster's soul to be broken off. Total soul removal results in something similar to a Persistent Vegetative State and is irreversible, while creating a Horcrux reduces the humanity of the caster, both in terms of morality/behaviour and appearance (evidenced by the once handsome Tom Marvolo Riddle becoming monstrous and snake-like in appearance over time). The damage of creating a Horcrux may be undone through remorse, but the process is so painful it can be fatal.
 * The victim of a Dementor's Kiss cannot become a ghost, since the soul has been lost. Presumably, the victim also cannot enter the afterlife, or possibly even Limbo. Similarly, the maker of a Horcrux cannot die, while the Horcrux(es) is/are intact, and if an unrepentant Horcrux maker is killed, he or she is trapped in Limbo and cannot enter the afterlife.
 * In, Lupin states "the only people that know what's under a Dementor's hood are in no state to tell us (being soulless)" but from the 5th movie and onward, they are shown without any hood at all. This is likely due to change of directors.
 * A species of wasp, , is named after the Dementor. This name was chosen to reflect the fact that the wasp uses a toxin to neutralise the neural behaviour of cockroaches and make them docile, as if their souls had been sucked out.
 * For the films they initially created puppets for the Dementors which were operated underwater to give them their floating on air effect. Ultimately these did not appear in the final edit and CGI Dementors were used instead.
 * Interestingly despite being considered natural allies to dark wizards, the Dementors did not side with the Death Eaters in the First Wizarding War nor did Voldemort appear to try and recruit them.
 * Some weeks before the release of the first film adaptation of Fantastic Beasts and Where to Find Them, Pottermore Featured "Beasts of the Week" The Dementor was the "Beast of the Week" on 21st September 2016, though Dementors are Non-Human Spiritous Apparitions.
 * The Dementors might be based on the Sluagh of Irish Folklore. The Sluagh are said to be the spirits of people so evil, that Hell rejected them. The Sluagh come in from the west like a flock of birds and try to find a house where a person is dying. They will try to snatch the soul of the dying person. The Irish often kept their windows shut to ward off the Sluagh. Like the Sluagh, the Dementors are ghostly, shadowy, evil creatures that try to steal the souls of their victims.

Portrayal in the movies
In the film series, Dementors are portrayed differently compared to how they were described in the books. In the books, they were described as tall hooded humanoid figures, whereas in the films, they appear as skeletal creatures wearing black robes.

Another notable difference is that the Dementors in the films can fly freely. This aspect was completely absent from the books, where they were merely gliding over the ground. This is most noticeable when the Dementors were intruding the first Quidditch match in the Prisoner of Azkaban. In the book, the Dementors were described as standing in the stadium, while in the film, they were purposefully pursuing a broomstick riding Harry Potter. Because of this, the corporeal Patronus Charm in  seems to work differently by sending a pulse at the Dementors flying in the air rather than charging at them on the ground.

Furthermore, the Dementors from the films appear to have a much more drastic effect on the environment compared to their book counterparts. In the films, the nearby surroundings of a Dementor are immediately covered by a layer of ice and any plant in the vicinity almost instantly withers away. The only explicit effect the book described Dementers were having in the environment is that they are accompanied by a cold mist. The first Dementor Harry encountered in the third film was able to open the Hogwarts Express without touching it, causing it to slide open with a wave of its hand, with some wizards and witches in the films also being able to perform similar feats. Also, the first Dementor seen in the fifth film was able to effortlessly lift Harry off the ground by the neck and pin him to a wall, showing great strength.

Foreign words for Dementor

 * Albanian: "Marroses"
 * Bulgarian: "Диментор"
 * Catalan: "Demèntor" (pronounced duh-MEN-toor)
 * Chinese:
 * Taiwan: 催狂魔 - cuīkuángmó - "drive-mad devil/demon"
 * Mainland: 摄魂怪 - shèhúnguài - "suck-soul devil/monster" 攝魂怪 in traditional characters
 * Czech: "mozkomor" - "plague of the brain"
 * Danish: "Dementor"
 * Dutch: "Dementor"
 * Finnish: "ankeuttaja", from "ankeus" - "drearyness"
 * French: "détraqueur" - "that which makes (things) go wrong or break down"
 * German: "Dementor"
 * Georgian: "დემენტორი" (დემენტორები); (pronounced dementori, plural: dementorebi)
 * Greek: "Παράφρονας" (pronounced "Parafronas") - from Greek "παράφρων" meaning "mentally ill".
 * Hebrew: "סוהרסן" (pronounced "Soharsan", plural: "סוהרסנים", "Soharsanim") - from "סוהר" ("prison warden") and "הרסן" ("destructive")
 * Hindi (India): दमपिशाच (damapishācha or dampishāch) - from dama = "house" and pishācha (a type of Hindu demon: see ).
 * Hungarian: "Dementor"
 * Icelandic: "Vitsuga" - The one who sucks out your mind, or sense of anything.
 * Indonesian: "iblis" - "demon of death and happiness remover"; see Iblis
 * Italian: "dissennatore" - "he who takes sanity away", from senno meaning 'mental sanity'
 * Japanese:
 * ディメンター - dimentā
 * 吸魂鬼 - "kyūkonki" - suck-soul ghost/demon (modeled after East Asian words for vampires)
 * Lithuanian: "Psichas" - Mental/Psycho
 * Latvian: Atprātotājs
 * Macedonian: Дементор
 * Norwegian: "Desperant" - One that brings out despair
 * Persian: "دیوانه ساز" - Maddening
 * Polish: "Dementor"
 * Portuguese:
 * Brazilian: "Dementador"
 * European: "Dementor" (plural: "Dementores")
 * Romanian: "Dementor"
 * Russian: "Дементор" (plural: Дементоры)
 * Slovak: "Dementor"
 * Slovenian: "Morakvar"
 * Spanish: "Dementor"
 * Swedish: "Dementor"
 * Thai: "ผู้คุมวิญญาณ" - "Poo-khum-win-yarn" - Soul Warden
 * Turkish: "Ruh Emici" - "soul-suckers"
 * Ukrainian: "Дементор" (plural: Дементори)
 * Vietnamese: "giám ngục Azkaban" - "prison guards of Azkaban"

Notes and references
Dementor Détraqueur Dementor Дементор סוהרסן Ankeuttaja Dementor 吸魂鬼