Noisy or mischievous spirit. The term poltergeist comes from the German words poltern (“to knock”) and geist (“spirit”) and refers to unexplained incidences of noises and knocks and moved, thrown, spilled, and broken objects. Unlike Ghosts and hauntings, poltergeist incidents usually do not involve sites of tragic, violent, or emotionally charged events or the spirits of people who died violently. Poltergeists generally are affiliated with a particular person, often an adolescent, and their manifestations typically are harmless but may be frightening and a nuisance. Their manifestations may last a few hours or more than a year, but typically they start and end abruptly. Poltergeist incidents have been recorded for many centuries. They include rocks raining from the skies; houses with mysterious rappings and other unexplained noises; vases and other fragile objects thrown and smashed; small fires with no known origin; and occasional physical attacks on persons; usually involving scratches, pinchings, bruises, and rarely sexual assaults.
One well-known 20th-century incident revolved around a young German secretary named Anne-Marie Schaberl. In the summer of 1967, while Anne-Marie was working, light bulbs began to burst in the offices and hallways, documents moved mysteriously from one room to another, heavy file cabinets moved out from the walls against which they had stood, and telephone records showed that an impossible number of calls was being made to a time-information number. Investigators were called in, including Dr. Hans Bender, psychologist and parapsychologist from Freiburg University, and two physicists from the prestigious Max Planck Institute for Plasmaphysics. They discovered that the incidents only occurred during office hours and only when Anne-Marie was present. The investigators absolutely ruled out the possibility that Anne-Marie was causing these events purposely. When Anne-Marie left for vacation and ultimately another job, the incidents abruptly stopped.