The Taboo

• Incantation: Unknown. The curse is placed upon a specific word, which then acts as the trigger.
• Pronunciation: Not applicable.
• Wand Movement: Unknown.
• Light: No light is produced by the spell itself; its effects are auditory and locational for the casters.
• Effect: A powerful and insidious curse that places a trace on a specific word. Whenever the Tabooed word is spoken, the spell breaks any protective enchantments in the vicinity and instantly alerts the casters to the speaker's precise location, allowing them to Apparate directly to them.
• Type: Dark Magic; specifically, a complex and powerful Curse.

The Taboo was a dark enchantment employed by Lord Voldemort and his Death Eaters during the height of the Second Wizarding War, specifically after they seized control of the Ministry of Magic. Voldemort placed the Taboo on his own name, “Voldemort.” This was a psychologically cunning tactic. After years of instilling fear associated with his name, most of the wizarding populace referred to him only as “You-Know-Who” or “He-Who-Must-Not-Be-Named.” Only those who did not fear the name — primarily members of the Order of the Phoenix and Harry Potter's closest allies — would dare to speak it aloud. By making the name itself a trigger for a tracking curse, Voldemort turned his opponents' bravery into a liability, effectively creating a self-identifying trap for his enemies. Known instances of the Taboo's activation include:

• Ron Weasley first explains the existence of the Taboo to Harry Potter and Hermione Granger, warning them that people have been captured for saying the name.
• Shortly after their escape from the Lovegoods' house, Harry Potter accidentally says “Voldemort” out of frustration. The Taboo curse immediately shatters Hermione Granger's extensive protective enchantments around their campsite. This leads to their swift capture by a gang of Snatchers led by the werewolf Fenrir Greyback.
• The trio's capture by Greyback's gang results in them being taken to Malfoy Manor, a pivotal event leading to the death of Dobby and their acquisition of Bellatrix Lestrange's wand.
• On the clandestine radio program Potterwatch, Kingsley Shacklebolt (under the codename “Royal”) warns listeners that the name “Voldemort” has been Tabooed, urging the resistance to avoid using it.

The magical knowledge required to cast such a far-reaching and powerful curse is undoubtedly advanced and falls under the category of extreme Dark Magic. It is likely a spell known only to a select few powerful dark wizards, with Lord Voldemort being its most notable user. There is no known counter-spell for the Taboo. The curse is potent enough to break through standard defensive magic, including the Protego Totalum, Salvio Hexia, and Muffliato charms that Hermione Granger used to protect their campsites. The only effective defence against the Taboo is to completely avoid speaking the enchanted word.

The term “taboo” is derived from the Tongan word tapu, meaning “forbidden,” “proscribed,” or “sacred.” In English, it refers to a strong social prohibition against a word, object, or action that is deemed improper or offensive. This perfectly describes Voldemort's magical enforcement of a prohibition on his own name, making the act of speaking it a punishable offense.

• In the film adaptation Harry Potter and the Deathly Hallows – Part 1, the effect of the Taboo is visualized. When Harry Potter says the name in a London café, a magical distortion ripples outwards, alerting Antonin Dolohov and Thorfinn Rowle. Later, when he says it in the woods, a similar effect summons Fenrir Greyback and the Snatchers. (film)