Literally, "noisy ghost." Whenever strange physical phenomena occur, such as objects flying through the air for no apparent reason, windows becoming blackened by an indefinable substance, or lights going on and off with no human hand controlling them, this is known as "poltergeist phenomena." Usually, parapsychologists consider poltergeist phenomena less the work of actual ghosts than the frustrated psychic energy of unhappy children or younger adolescents. The story of the Amityville Horror was considered poltergeist phenomena until it was revealed to be a hoax.
From the German for "noisy ghost", the term generally encompasses all forms of alleged spirit activity characterised by loud noises and fantastic displays of "apports", "teleportation", "levitation", and "rappings". Clinical parapsychology, however, limits the use of the term to describe possible cases of "Recurrent Spontaneous Psychokinesis" or "Repressed Psychokinetic Energy", in which the phenomena experienced is identical in nature, but the source is attributed to an "agent" who serves as the center focus point for the activity.
A general term applied to a variety of site-, or sometimes person-, specific physical phenomena. These can include temperature variations, anomalous sounds, and movement of physical objects. The word 'poltergeist' literally means 'noisy spirit' and was coined back when such phenomena were thought to be due to the presence of some sort of mischievous entity. Currently, poltergeist phenomena are usually considered to be related either to unusual physical conditions at the affected site, or to be related to psychokinesis. Anecdotal reports suggest that many poltergeist focus on an individual under some form of emotional stress.