GHOST

n. spirit; phantom; shadow; hint, trace; ghost writer (Slang)

v. haunt; move like a ghost; sail along smoothly; ghostwrite (a book, speech, etc.)

n. Academy Award-winning film starring Demi Moore and Patrick Swayze (released in 1990)

A ghost is defined as the apparition of a deceased person, frequently similar in appearance to that person, and usually encountered in places she or he frequented, or in association with the person's former belongings. The word "ghost" may also refer to the spirit or soul of a deceased person, or to any spirit or demon. Ghosts are often associated with hauntings, which is, according to the Parapsychological Association, "the more or less regular occurrence of paranormal phenomena associated with a particular locality (especially a building) and usually attributed to the activities of a discarnate entity; the phenomena may include apparitions, poltergeist disturbances, cold drafts, sounds of footsteps and voices, and various odours."
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Noun
1. a mental representation of some haunting experience; "he looked like he had seen a ghost"; "it aroused specters from his past"
(synonym) shade, spook, wraith, specter, spectre
(hypernym) apparition, phantom, phantasm, phantasma, shadow
(derivation) haunt, obsess
2. a writer who gives the credit of authorship to someone else
(synonym) ghostwriter
(hypernym) writer, author
(derivation) ghostwrite
3. the visible disembodied soul of a dead person
(hypernym) soul, psyche
(hyponym) poltergeist
4. a suggestion of some quality; "there was a touch of sarcasm in his tone"; "he detected a ghost of a smile on her face"
(synonym) touch, trace
(hypernym) suggestion, proposition, proffer
Verb
1. move like a ghost; "The masked men ghosted across the moonlit yard"
(hypernym) travel, go, move, locomote
2. haunt like a ghost; pursue; "Fear of illness haunts her"
(synonym) haunt, obsess
(hypernym) preoccupy
(derivation) shade, spook, wraith, specter, spectre
3. write for someone else; "How many books have you ghostwritten so far?"
(synonym) ghostwrite
(hypernym) author
(derivation) ghostwriter
(classification) writing, authorship, composition, penning

(v. t.)
To appear to or haunt in the form of an apparition.
  

(v. i.)
To die; to expire.
  

(n.)
The spirit; the soul of man.
  

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

(n.)
Any faint shadowy semblance; an unsubstantial image; a phantom; a glimmering; as, not a ghost of a chance; the ghost of an idea.
  

(n.)
A false image formed in a telescope by reflection from the surfaces of one or more lenses.
  

[Folklore] A disembodied spirit. The term is usually applied to the human soul after death. It is used interchageably with such words as apparition, phantom, specter, shade, and revenant.