This magical item, essentially an object that stores a part of a dark wizard’s or witch’s soul, plays a crucial role in the later Harry Potter books, though we also find out one played a significant role in Harry Potter and the Chamber of Secrets.
The name is unique to Rowling’s work and doesn’t even appear in print until the sixth book, Harry Potter and the Half-Blood Prince, where it is described as “receptacle in which a Dark wizard has hidden a fragment of his soul for the purposes of attaining immortality”. Although a Horcrux can be made from anything, Voldemort prefers to use objects of immense personal, sentimental, or historical value.
To create a Horcrux a wizard must deliberately murder someone. This soul-rending act lets the wizard place a part of his soul into the Horcrux, and thus protect himself from death. After the young Voldemort learned how to make a Horcrux from a book in Dumbledore's office after asking Horace Slughorn, his Potions Master while at Hogwarts, about the subject, he used his diary as one, though Harry ultimately destroyed it in Chamber of Secrets.
We find out more in Deathly Hallows, where Hermione discovers that the book Secrets of the Darkest Arts, a horrible book according to her, explains the process in full. This book also describes how difficult it is to destroy a properly protected Horcrux, requiring such rare objects as a basilisk fang or phoenix teardrop to do it.
The idea of a Horcrux is not unique to Harry Potter. The Ring of Power in Tolkien’s Middle Earth is a similar magical object, both with a will of its own and with its destruction destroying its creator Sauron. It is also similar to the Russian myth of Koschei, who supposedly hid his soul in an attempt to achieve immortality.
Rowling has not explained how she came up with this peculiar name. One might suppose it is a combination of horrible and curse, or similar such words. Words like horrible, horrific, and horrid all come from the Latin horridus, the past participle and adjective form of the verb horrere, meaning to shudder or (of hair) to stand on end. Similarly, crux may come from the Latin word crux, meaning cross. Crosses were used by the Romans for crucifixion (literally, put on a cross), and Latin has several idioms with crux that mean torment: abi in malam crucem, for instance.
But this is still peculiar. So many of Rowling’s names are the result of ingenious word play or come from clear language roots. The Unforgivable Curses, the various spells, even the names of the four Houses at Hogwarts, to name but a few, have Latin or Greek roots combined with familiar words.
The translators of Harry Potter and the Half-Blood Prince kept Horcrux essentially the same in languages that use the Roman alphabet, as can be seen below.
|Japanese||ホークラックス (pronounced hookurakkusu)|
Japanese simply uses a phonetic version of the word Horcrux in its native Katakana writing system, and Chinese uses characters that represent what the Horcrux is in simple terms: spirit/soul container. So Horcrux is not especially remarkable, clear, or clever in the translations either.
Perhaps Horcrux is meant to stand out because of what it is. This method of offloading a portion of the soul so as to achieve an artificial form of immortality is at the base of Lord Voldemort’s evil and is a fundamental moral thread in all the Harry Potter novels. From the first book when Harry sees Voldemort as Quirrel killing a unicorn and drinking her blood to heal himself to the resurrection scene at the end of the fourth book, the idea of immortality at any cost is a dominant theme.
By choosing a unique yet not transparent name, Rowling may be telling us far more about Voldemort's evil than if she had used something more sinister.