ghost, shade, spook, wraith, specter, spectre (noun)

a mental representation of some haunting experience

"he looked like he had seen a ghost"; "it aroused specters from his past"

ghostwriter, ghost (noun)

a writer who gives the credit of authorship to someone else

ghost (noun)

the visible disembodied soul of a dead person

touch, trace, ghost (verb)

a suggestion of some quality

"there was a touch of sarcasm in his tone"; "he detected a ghost of a smile on her face"

ghost (verb)

move like a ghost

"The masked men ghosted across the moonlit yard"

haunt, obsess, ghost (verb)

haunt like a ghost; pursue

"Fear of illness haunts her"

ghost, ghostwrite (verb)

write for someone else

"How many books have you ghostwritten so far?"

ghost (Noun)

The spirit; the soul of man.

ghost (Noun)

The disembodied soul; the soul or spirit of a deceased person; a spirit appearing after death; an apparition; a specter.

ghost (Noun)

Any faint shadowy semblance; an unsubstantial image; a phantom; a glimmering.

ghost (Noun)

A false image formed in a telescope, camera, or other optical device by reflection from the surfaces of one or more lenses.

ghost (Noun)

An unwanted image similar to and overlapping or adjacent to the main one on a television screen, caused by the transmitted image being received both directly and via reflection.

ghost (Noun)

A ghostwriter.

ghost (Noun)

A nature spirit, ancestor or house spirit (see brownie ) revered in Heathenry.

ghost (Noun)

An unresponsive user on IRC, resulting from the user's client disconnecting without notifying the server.

ghost (Noun)

an image of a file or hard disk.

ghost (Verb)

To haunt.

ghost (Verb)

To ghostwrite.

ghost (Verb)

to copy a file or hard drive image.

ghost (Noun)

An understudy.

ghost (Noun)

A covert (and deniable) agent.

Ghost

In traditional belief and fiction, a ghost is the soul or spirit of a dead person or animal that can appear, in visible form or other manifestation, to the living. Descriptions of the apparition of ghosts vary widely from an invisible presence to translucent or barely visible wispy shapes, to realistic, lifelike visions. The deliberate attempt to contact the spirit of a deceased person is known as necromancy, or in spiritism as a séance. The belief in manifestations of the spirits of the dead is widespread, dating back to animism or ancestor worship in pre-literate cultures. Certain religious practices—funeral rites, exorcisms, and some practices of spiritualism and ritual magic—are specifically designed to rest the spirits of the dead. Ghosts are generally described as solitary essences that haunt particular locations, objects, or people they were associated with in life, though stories of phantom armies, ghost trains, phantom ships, and even ghost animals have also been recounted.

Ghost

A ghost is the soul or spirit of a dead person or animal that is believed to be able to appear to the living. In ghostlore, descriptions of ghosts vary widely, from an invisible presence to translucent or barely visible wispy shapes to realistic, lifelike forms. The deliberate attempt to contact the spirit of a deceased person is known as necromancy, or in spiritism as a séance. Other terms associated with it are apparition, haunt, phantom, poltergeist, shade, specter, spirit, spook, wraith, demon, and ghoul. The belief in the existence of an afterlife, as well as manifestations of the spirits of the dead, is widespread, dating back to animism or ancestor worship in pre-literate cultures. Certain religious practices—funeral rites, exorcisms, and some practices of spiritualism and ritual magic—are specifically designed to rest the spirits of the dead. Ghosts are generally described as solitary, human-like essences, though stories of ghostly armies and the ghosts of animals rather than humans have also been recounted. They are believed to haunt particular locations, objects, or people they were associated with in life. According to a 2009 study by the Pew Research Center, 18% of Americans say they have seen a ghost.The overwhelming consensus of science is that there is no proof that ghosts exist. Their existence is impossible to falsify, and ghost hunting has been classified as pseudoscience. Despite centuries of investigation, there is no scientific evidence that any location is inhabited by the spirits of the dead. Historically, certain toxic and psychoactive plants (such as datura and hyoscyamus niger), whose use has long been associated with necromancy and the underworld, have been shown to contain anticholinergic compounds that are pharmacologically linked to dementia (specifically DLB) as well as histological patterns of neurodegeneration. Recent research has indicated that ghost sightings may be related to degenerative brain diseases such as Alzheimer's disease. Common prescription medication and over-the-counter drugs (such as sleep aids) may also, in rare instances, cause ghost-like hallucinations, particularly zolpidem and diphenhydramine. Older reports linked carbon monoxide poisoning to ghost-like hallucinations.In folklore studies, ghosts fall within the motif index designation E200–E599 ("Ghosts and other revenants").