>Horcrux
A Horcrux was an object in which a Dark Wizard or Witch had hidden a fragment of his or her soul in order to become immortal.[3] Horcruxes could only be created after committing murder, the supreme act of evil. The process for the creation of a Horcrux involved a spell and a horrific act was performed soon after the murder had been committed. Given that Horcruxes were precious to those who made them, there were usually protective measures made to prevent them from being stolen or destroyed, such as counter-charms and curses. The Horcrux was considered to be the most terrible of all dark magic
https://harrypotter.fandom.com/wiki/Horcrux