The most common type of nightmare or bad dream is the one in which you are being chased or hunted down by something or someone. According to Jung, being chased or stalked as prey is a primal memory of your human collective unconscious and may refer to early times in the history of humankind when it was common to be chased, often to the death, by an animal.
If you are being chased in your dream it is important to think about who or what was chasing you, and then ask yourself whether there is anyone or anything in your life that reminds you of your pursuer.... The Element Encyclopedia
Memories, experiences, emotions and patterns from the past, which haunt the dreamer. It may represent attitudes or patterns of behavior which were once alive, but now suppressed.
To see another person as a ghost or spirit relates to the dreamer’s reaction and thoughts about that person’s influence on the dreamer. Some believe that the ghosts in their dreams are real representations of the dead. This is an unlikely explanation of this dream. More likely the ghost is representing a part of you that is unclear and that you do not understand. At times, ghosts represent those things that unattainable or fleeting. Demonic type of ghost images may represent your negative tendencies, unpleasant parts of personality or your “shadow.” Old superstition based dream interpretations say that dreaming of friendly ghosts is a lucky omen, and that you should be receiving unexpected good luck. On the other hand, if you were very frightened by the ghost in your dream, then others will try to impose their will on you and you must be vigilant in order to stand up to it. ... The Bedside Dream Dictionary
The ghost in your dream represents a part of yourself that is unclear to you, and that you do not understand. At times, ghosts represent those things that we can no longer obtain and that are fleeting. Traditionally, dreaming of friendly ghosts is a lucky omen, and that you should be receiving unexpected good luck. On the other hand if you were very frightened by the ghost in your dream, then others will try to impose their will on you and you must be vigilant in order to stand up to it.... Tryskelion Dream Interpretation
Even the most prosaic and materialistic of us have dreams that include supernatural creatures or incidents.
Ghosts, witches, out-of-body experiences, UFOs, haunted houses and a whole plethora of spirits, creatures and unexplained phenomena exist in the world of the supernatural. When these images appear in your dreams, they can be unsettling, especially when psychics claim that they are connected with the supernatural. Even though there is no evidence to suggest this is the case, the mysterious and often bizarre nature of dreams has led many to interpret dreams as supernatural gifts or messages, as predictions of the future or as messages from the past. Modern oneiromancy, the prediction of the future through the interpretation of dreams, is a tradition that has its roots in pagan and ancient Greek and Roman thought, as well as in the Jewish and Christian religions.
Freudians and Jungians, together with most other dream analysts, reject the supernatural origin of dreams. Their view is that dreams bubble up from the unconscious mind and are metaphors for events or emotions occurring in our waking lives. Theologians, however, continue to admit the possibility that dreams may be supernatural or divine in origin. Whether or not you believe dreams have a supernatural origin, if you are experiencing such dreams, your unconscious might be urging you to be more open-minded towards unexplained phenomena; alternatively, they might be suggesting a need for radical change in your life or attitude. See also MIND, BODY, SPIRIT; NIGHTMARES; SURREALISM AND FANTASY.... The Element Encyclopedia