In ghostlore, a poltergeist ( or ; German for "rumbling ghost" or "noisy spirit") is a type of ghost or spirit that is responsible for physical disturbances, such as loud noises and objects being moved or destroyed. Most claims or fictional descriptions of poltergeists show them as being capable of pinching, biting, hitting, and tripping people. They are also depicted as capable of the movement or levitation of objects such as furniture and cutlery, or noises such as knocking on doors. Foul smells are also associated with poltergeist occurrences, as well as spontaneous fires and different electrical issues such as flickering lights.

They have traditionally been described as troublesome spirits who haunt a particular person instead of a specific location. Some variation of poltergeist folklore is found in many different cultures. Early claims of spirits that supposedly harass and torment their victims date back to the 1st century, but references to poltergeists became more common in the early 17th century.