Poltergeist

One of the more mischievous types of Spirit are the Poltergeists. They generally seek to frighten the living by tossing objects about and making a nuisance of themselves.

Poltergeists are similar to Ghosts, but they love to frighten mortals and play tricks on them. Why some of the dead become Ghosts and others Poltergeists is a subject of debate.

Source
pg. 65
 * Warhammer Fantasy RPG 2nd ED -- Old World Bestiary

pg. 109