In mythology and folklore, a vengeful ghost or vengeful spirit is said to be the spirit of a dead person who returns from the afterlife to seek revenge for a cruel, unnatural or unjust death. In certain cultures where funeral and burial or cremation ceremonies are important, such vengeful spirits may also be considered as unhappy ghosts of individuals who have not been given a proper funeral.
Ghostlore is the body of traditional beliefs and folklore surrounding ghosts and hauntings. Such tales often feature souls of the deceased that are believed to linger in the physical world, either to communicate with the living or to seek vengeance for past wrongs. Ghostlore is a widespread phenomenon, and narratives of hauntings and ghostly encounters are found in cultures around the world.
The term "ghost" eludes a singular definition; its meaning has evolved across cultures, shaped by various interpretations rooted in religious beliefs, folklore, and historical context. Interpretations of ghosts vary based on religious beliefs, cultural values, and historical contexts.