Wizards, Witches and Beings: A
Abbott
Family name on a headstone in the graveyard in Godric’s Hollow, probably ancestors of Hannah, since wizarding families tended to live close together in certain villages after the Statute of Secrecy went into effect in 1692 (DH16).
Abbott,
Hannah 
(b. 1980)
Hufflepuff, 1991 - 1998, prefect 1995 - 1998
Hufflepuff student in Harry's year and member of Dumbledore's
Army. Sadly, Hannah's mother was killed
by Death Eaters (HBP11)
during her sixth year at Hogwarts. Hannah left Hogwarts and did not returned
to school that year, but answered the call to fight in the Battle
of Hogwarts (DH31).
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Abbott, Mrs.
(d. 1996)
Hannah's mother. She was found dead in
the fall of 1996,
murdered by Death Eaters (HBP11).
Abercrombie,
Euan 
(b. 1984)
Gryffindor, 1995 -
2002
A small boy with prominent ears; it's implied that at the beginning
of his first year that he believed the Daily
Prophet's smear campaign against Harry (OP11).
Ackerley,
Stewart
(b. 1983)
Hogwarts student. Ravenclaw, 1994 - 2001 (GF12).
Aesalon,
Falco
Ancient Greek
The first recorded example of an Animagus.
He could transform himself into a falcon (fw).
"falco" = L. "falcon"; in Muggle science this word is part of the scientific name of the species.
Agnes
Patient in the Janus Thickey ward for permanent spell damage at St. Mungo's Hospital along with the Longbottoms, Broderick Bode (now deceased) and Gilderoy Lockhart. Agnes' entire head is covered with fur and she barks instead of speaking (OP23). The Healer told her that her son would soon visit and had sent her several Christmas gifts.
Agrippa,
Cornelius

(1486 - 1535)
Full name: Heinrich Cornelius Agrippa von Nettesheim. Agrippa appears on a Chocolate Frog trading card, which reads "celebrated wizard imprisoned by Muggles for his writing, because they thought his books were evil" (fw33, PS6, CF). In PS6, Ron tells Harry that 'Agrippa' is one of the Chocolate Frog cards he is missing from his collection.
In the Muggle version of history, Agrippa was a German soldier and physician, and an adept in alchemy, astrology, and magic. In his book De Occulta Philosophia (1531), Agrippa encouraged the study of magic, explaining the world in terms of cabalistic analyses of Hebrew letters and Pythagorean numerology; he believed that magic was the best means to know God and nature.
Legend has it that he "was always accompanied by a familiar in the shape of a large black dog." It was also said that "at the inns where he stayed, Agrippa paid his bills with money that appeared genuine enough at the time, but which afterward turned to worthless horn or shell, like the fairy money which turned to earth after sunset." (Source: Encyclopedia of Occultism and Parapsychology, 5th ed.)
Alderton
Alleged Muggle-born accused of “stealing magic” and sent to Azkaban by the Muggle-born Registration Commission in the days when the Ministry was controlled by Death Eaters. Claimed to be the son of Arkie Alderton, a wizard (DH13).
Alderton,
Archibald
(1568 - 1623)
Famous for blowing up the hamlet of Little Dropping in Hampshire while attempting to magically mix a birthday cake (fw40).
Alderton, Arkie
Well-known broomstick designer (DH13).
Probably the current proprietor (or his namesake) of "Arkie
Alderton's Kwik-Repair Shop" for magical brooms (BLC).
Algie
Neville's great-uncle, see Longbottom family
Alecto, see Carrow, Alecto
Altheda
The second of three witches in the story "The Fountain of Fair Fortune" from The Tales of Beedle the Bard. According to the Amazon.com paraphrase, Altheda was a witch who had lost confidence in herself after being robbed and humiliated, and went to find the fabled fountain for a cure for her feelings of helplessness. On her way she meets two other witches, Asha and Amata, and even though just one may bathe, the three decide to help each other get to the fountain. After passing through three obstacles, Asha collapses and Altheda quickly mixes a potion that not only revives her, but also cures her "incurable" malady. When the fountain is reached, Altheda realizes that knowledge of her healing skills have made her feel powerful and hopeful again and she no longer needs the fountain (TBB/FFF).
Name possibly derived from 'Althos,' Greek for 'healing,' and related to the female names Althea/Althaea.
Amata
The third of three witches in the story "The Fountain of Fair Fortune" from The Tales of Beedle the Bard. In the Amazon.com paraphrase, Amata was a witch seeking a cure from the fountain for the grief and longing caused when she was deserted by her beloved. As she journeys to the fountain (which will only let one person bathe), she meets two other witches, Asha and Altheda , and rescues a Muggle knight named Sir Luckless. The third obstacle before the fountain was a stream where the women are told to leave a treasure of their past. Amata uses her wand to pull memories of her faithless lover and deposit them in the stream. To her surprise, once her judgment is unclouded, she realizes that her lover was cruel and unworthy of her and that she has cured herself. Fortunately for Sir Luckless, the other two women have similar epiphanies, and he is luckless no more. He bathes in the fountain (in full armor, no less) and Amata begins to fall in love with him (TBB/FFF).
Amata means 'beloved' in Italian.
Amycus, see Carrow, Amycus
Andros the Invincible
Ancient Greek, dates unknown
Alleged to have been the only known wizard to produce a Patronus the size of a giant (fw).
Archie
Old wizard with a penchant for flowered nightgowns; Archie refused to wear trousers at the World Cup campground, saying that he liked "a healthy breeze around his privates" (GF7).
Arcus
One of two wizards thought to have taken the Elder Wand from Loxias (DH21).
Asha
The first of three witches in the story "The Fountain of Fair Fortune" from The Tales of Beedle the Bard. In the account given on Amazon.com, Asha is a witch with an incurable malady who seeks wellness at the fountain. Along the way she meets two other women, Altheda and Amata, and even though the fountain will only let one of them bathe, they decide to help each other out. Asha helps them through the first obstacle, a worm that demands proof of their pain; her tears of frustration eventually win them passage. After the third and final obstacle, however, Asha collapses. Altheda brews a potion that not only revives Asha, it cures her of her illness, and Asha realizes she doesn't need the fountain after all. (TBB/FFF).
Asha means 'wish, desire, hope' in Hindi, and 'life' in Swahili.
Aubrey, Bertram
Hogwarts
student, 1970s
James Potter and Sirius
Black once received detention for
hexing Aubrey and causing his head to grow twice its normal size (HBP24).
"aunt" For any character known only as "aunt [given name]", please look the character up by her given name.
Avery
(b. late 1920s)
One of the earliest (c.1955) members of the Death Eaters (HBP20); attended Hogwarts with Tom Riddle (HBP17). Probably related (father/son?) to the Avery that attended Hogwarts with Severus Snape.
Avery 

(b. late 1950s or early 1960s)
Slytherin (GF27).
Attended Hogwarts with Severus
Snape (GF27). A Death
Eater who "wormed his way out of trouble by saying he acted under
the Imperius Curse" (GF27);
he was punished by Voldemort with the Cruciatus
Curse once Voldemort regained a functioning
body (GF33). Probably related
(father/son?) to the Avery that attended Hogwarts with
Tom Riddle.