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Amortality is the condition of never having died and being unable to die, as an amortal entity was never alive to begin with. Amortality is a known trait of non-beings.
As amortality refers to entities that have never been alive from the beginning, it is different from "immortality", which means a living being gaining the impossibility to die.
Poltergeists are amortal, as they have been described as "indestructible spirits of chaos", and are known to differ from ghosts in that they were never alive at one time.Boggarts and Dementors, being creatures that were never truly alive to begin with and seemingly indestructible, are other types of amortal creatures.