This is a very brief lisitng of paranormal terms/definitions:
Agent – a person whom poltergeist activity is focused on or emanating from

Apparition - a spirit-like image of a person that materializes without a physical body present

Aura – an emanation of light (seen or unseen) that surrounds a person or object, often thought to be a reflection of a person’s personality

Banshee – a wailing spirit that may appear to be in multiple places at the same time

Case Study – an in-depth investigation of a location or situation

Clairvoyance – having the ability to see (in the form of mental imagery and intuition) events or entities that cannot be perceived by the senses  (See also ESP)

Collective Apparition - a type of paranormal sighting where multiple individuals see the same apparition or phenomena

Demon - a being or entity often spoken of in religious text as pure evil

Doppelganger – an exact spirit double of a person, considered to be a negative entity

Earthbound –refers to a spirit that is unable to cross over to the other side at the time of death and remains on earth

Ectoplasm – a substance associated with spirit manifestations

Electronic Voice Phenomenon (EVP) – voices and/or sounds that are captured on some form of electronic recording device

Elementals – entities or spirits sometimes also called “Earth Spirits” (i.e., elves, fairies and trolls)

EMF Detector (magnetometer, gauss meter) - instrument used to measure the strength and direction of an electronic and/or magnetic field (also called a magnetometer or gauss meter)

Extra Sensory Perception (ESP) - perception and communication without use of the physical senses

Exorcism – removal or banishment of an entity(ies) thought to possess or haunt a location or human

Gauss meter (EMF, magnetometer) - instrument used to measure the strength and direction of an electronic and/or magnetic field (also called an EMF or magnetometer)

Ghost –an apparition or entity that is thought to be a deceased human's spirit/soul

Ghost Hunting – a strategic investigation at a location that may or may not have paranormal activity, no verifiable witness to activity prior to the investigation (goal is to find paranormal activity)

Ghost Investigation – a strategic investigation at a location that has verifiable witnesses to/reports of paranormal activity (goal is to try and verify claims of paranormal activity)

Ghoul – dark, demonic or parasitic entities

Hallucination – the perception of sights and sounds that do not actually exist

Haunting – reoccurring unexplained paranormal phenomena – may include spirits, shadows, moving objects, unexplained sounds

Intelligent haunting - haunting in which the paranormal activity/entity/energy interacts and may respond to individuals involved

Magnetometer (EMF, gauss meter) - instrument used to measure the strength and direction of an electronic and/or magnetic field (also called an EMF or gauss meter)

Materialization or manifesting – act of forming something solid from the air, when a part or the entire ghost/spirit becomes visible

Medium - an individual who professes to be able communicate with spirits or can act as an intermediary between the world of the living and the dead

Orb – a photographed ball of light that may represent an entity or a bundle of energy,  orbs may appear as balls of light on video or film though often they are not seen at the time

Ouija Board – a printed board with letters, numerals, and words used to receive spirit communications by use of a movable marker or planchette

Paranormal – refers to something that is beyond scientific explanation and it out of the normal scope of human experiences

Parapsychology - the study of evidence relating to psychological phenomena

Percipient - person who sees (i.e., perceives) an apparition.

Phantom - entity that is seen/heard/felt/sensed but has no physical reality (i.e., ghost)

Poltergeist - a non-human entity literally meaning "noisy ghost,” usually more destructive than human ghosts (more recent theory suggests that poltergeist activity, at least in some instances, may be subconscious energy manifestations (PK) emanated by an adolescent agent)

Provoke (provoking) - to try and draw out or encourage an entity to communicate or materialize by means of making it angry

Psychic - person who can detect psychic forces, having above average ESP abilities.

Psychokinesis (PK) - power of the mind to affect matter without physical contact

Residual - type a haunting in which the paranormal activity/entity/energy replays over and over like a movie, this type of activity does not interact with individuals (also known as an anniversary ghost/haunting)

Séance - gathering of individuals, generally lead by a medium, to communication with non-living entities

Specter – a ghostly apparition; a phantom (see also ghost, phantom and ghoul)

Spiritualism - belief system that the dead are able to communicate with the living through the help of a medium

Supernatural - of or relating to existence outside the natural world, unlike paranormal, the term "supernatural" often refers to divine or demonic involvement

Telekinesis - movement of objects by scientifically unexplainable means

Vortex – unexplainable funnel or rope-like image in photographs

White Noise – acoustical or electrical noise with an intensity that is the same at all frequencies within a given band

For more complete listings of paranormal terminology click on the following links:
http://www.mdani.demon.co.uk/para/paraglos.htm
http://www.the-atlantic-paranormal-society.com/articles/general/glossary.html