Apparition: An experience usually visual but sometimes in other sense-modalities in which there appears to be present a person or animal (deceased or living) and even inanimate objects such as carriages and other things, who/which is in fact out of the sensory range of the experient; often associated with spontaneous extrasensory perception, for example, in connection with an agent who is dying or undergoing some other crisis (in which case, it is likely to be termed a “crisis apparition,” or in connection with haunting (in which case, it is likely to be referred to in non-technical contexts as a “ghost”) 
An apparition is an act or instance of appearing, including:
- a religious vision such as a Marian apparition; or
- certain ostensibly paranormal experiences such as Ghosts, Doppelgänger or Bilocation; or
- any other Apparitional Experience (i.e. anomalous, quasi-perceptual experience).
- Parapsychology by Michael A. Thalbourne, Republished by Puente Publications, Charlottesville, VA, USA, 2003