a desembodied spirit, esp. of a dead person who is supposedly able to manifest itself to the living in various ways
That sounds pretty good to me. The term "ghost" or "entity" is used to define a wide range of paranormal activity. An apparation, poltergeist, floating orb of light, or a strange noise emanating from what's believed to be a "haunted" house or location. There are many different terms when reffering to a ghost or paranormal activity so I will go over some.
Ghosts and apparations- a ghost is usually used when it comes to the visual appearance of a human or animal that has died. An apparation usually refers tothe visual appearance of a spirit or unusual phenomenon that doesn't necessarily take on the shape of a human form. These terms are used interchaneably by nonexperts. Basically all ghosts can be considered apparations, but not all apparations can be considered ghosts. The terms "phantom", "spook", "phantasm", "vision", and "poltergeist" are also used to describe the visual appearance of a ghost or apparation.
There are a few different types of apparations:
The apparation of a person who has been dead for more than
12-48 hours and are visiting for only a moment to visit a loved one
A living person who is having an OBE (out of body experience)
Apparations that visit us from another place or time that
seem confused or scared by their visit
Apparations of a human that haunts a location and may create
poltergeist phenomena (poltergeist phenomena involves interaction
with the physical enviroment).
Poltergeists-The word "poltergeist", when trabslated from German means "noisy ghost". A poltergeist may sometimes show itself as an apparation or ghost, but poltergeists are manly known for interacting with the physical enviroment. They tend to make noise and move things around. Poltergeists have been reported to levatate objects, make things disappear and re-appear, start fires, throws objects across rooms, and cause unexplainable sounds. In some theories it is said that not all poltergeist phenomena is caused by a deceased human, but is also caused by a living person who has phsycic or telekinetic abilities. Contrary to popular belief (and what has been commonly portrayed in horror movies), poltergeists aren't always evil. There have been very few insidents where a person has been harmed or killed by a poltergeist. However, they are considered to be more dangerous than ghosts and apparations.