ghost

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The spirit of a dead person, especially one believed to appear in bodily likeness to living persons or to haunt former habitats.
2. n. The center of spiritual life; the soul.
3. n. A demon or spirit.
4. n. A returning or haunting memory or image.
5. n. A slight or faint trace: just a ghost of a smile.
6. n. The tiniest bit: not a ghost of a chance.
7. n. A faint, false image, as:
8. n. A secondary image on a television or radar screen caused by reflected waves.
9. n. A displaced image in a photograph caused by the optical system of the camera.
10. n. A false spectral line caused by imperfections in the diffraction grating.
11. n. A displaced image in a mirror caused by reflection from the front of the glass.
12. n. Informal A ghostwriter.
13. n. A nonexistent publication listed in bibliographies.
14. n. A fictitious employee or business.
15. n. Physiology A red blood cell having no hemoglobin.
16. v. Informal To engage in ghostwriting.
17. v. To move noiselessly like a ghost: "Two young deer ghosted out of the woods” ( Nancy M. Debevoise).
18. v. To haunt.
19. v. Informal To ghostwrite: was hired to ghost the memoirs of a famous executive.

Century Dictionary and Cyclopedia

1. n. Breath; spirit; specifically, the breath; the spirit; the soul of man.
2. n. The soul of a dead person; the soul or spirit separate from the body; more especially, a disembodied spirit imagined as wandering among or haunting living persons; a human specter or apparition.
3. n. A spirit; a demon.
4. n. A spirit in general; an unearthly specter or apparition.
5. n. A dead body.
6. n. A mere shadow or semblance.
7. n. In optics, a spot of light or secondary image caused by a defect of the instrument, generally by reflections from the lenses.
8. n. Specifically In photography, a glint of light cast by the lens on the focusing-glass or on the plate during exposure, in the latter case producing a more or less defined opaque spot. It results usually from the presence of a too strongly illuminated surface or object in or near the field of the lens. Also called flare.
9. n. An order founded at Montpellier, France, about the end of the twelfth century, and united to the Order of St. Lazarus by Pope Clement XIII.
10. n. A Neapolitan order. See Order of the Knot, under knot
11. n. Synonyms Ghost, Shade, Apparition, Specter, Phantom, Phantasm. Ghost is the old word for the disembodied spirit, especially as appearing to man: as, the ghost of Hamlet's father; the ghost of Banquo. Shade is a soft and poetic word for ghost: as, the shade of Creüsa appeared to Æneas. An apparition is a ghost as appearing to sight, perhaps suddenly or unexpectedly; it may also be a fancied appearance, while a ghost is supposed to be real: as, Jupiter made a cloud into an apparition of Juno; Macbeth saw an apparition of a dagger; the witches showed him an apparition of a crowned child. A specter is an alarming or horrifying preternatural personal appearance, having less individuality, perhaps, than a ghost or shade, but more than an apparition necessarily has. A phantom has an apparent, not a real, existence; it differs from a phantasm in emphasizing the unreality simply and in representing a single object, while phantasm emphasizes the deception put upon the mind, and may include more than one object.
12. To appear to in the form of ghost; haunt as a spirit or specter.
13. To give up the ghost; die; expire.
14. n. One who does literary, legal, or artistic work for another, who gets all the credit; one who ‘devils’ for another.
15. n. A false line in a diffraction-spectrum caused by certain periodic irregularities in the ruling of the grating which produces the spectrum. Ghosts usually occur in pairs accompanying a conspicuous line on each side of it and near it. See grating.
16. n. A red blood-corpuscle from which the red coloring-matter or hemoglobin has escaped.

Wiktionary

1. n. rare The spirit; the soul of man.
2. n. The disembodied soul; the soul or spirit of a deceased person; a spirit appearing after death; an apparition; a specter.
3. n. Any faint shadowy semblance; an unsubstantial image; a phantom; a glimmering.
4. n. A false image formed in a telescope, camera, or other optical device by reflection from the surfaces of one or more lenses.
5. n. 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.
6. n. A ghostwriter.
7. n. Internet An unresponsive user on IRC, resulting from the user's client disconnecting without notifying the server.
8. n. computing an image of a file or hard disk.
9. n. theater An understudy.
10. n. espionage A covert (and deniable) agent.
11. n. The faint image that remains after an attempt to remove graffiti.
12. v. obsolete, transitive To haunt; to appear to in the form of apparition.
13. v. transitive, intransitive To ghostwrite.
14. v. computing to copy a file or hard drive image.

GNU Webster's 1913

1. n. obsolete The spirit; the soul of man.
2. n. The disembodied soul; the soul or spirit of a deceased person; a spirit appearing after death; an apparition; a specter.
3. n. Any faint shadowy semblance; an unsubstantial image; a phantom; a glimmering
4. n. A false image formed in a telescope by reflection from the surfaces of one or more lenses.
5. v. obsolete To die; to expire.
6. v. obsolete To appear to or haunt in the form of apparition.

WordNet 3.0

1. v. haunt like a ghost; pursue.
2. n. a writer who gives the credit of authorship to someone else
3. n. a suggestion of some quality
4. n. a mental representation of some haunting experience
5. v. move like a ghost
6. n. the visible disembodied soul of a dead person
7. v. write for someone else