What is the difference between a poltergheist and a ghost?

This could be completely wrong information but what I believe is that a poltergeist has some sort of special connection to the land and a ghost has some sort of special connection to the home or people in it. As I said, just a guess. Anyone else have an idea??

This question of meanings and semantics comes up a lot in spiritual work. Seems like when my friends and I get together, we spend half (or more) of the time just defining what we mean when we use a particular term. Different people use different terms to mean different things, but here's the sense I've always had about it:

To me, a "ghost" is specifically the spirit of a deceased person. Implicit in the term is a certain kind of transparency, that the ghost is ghostly because it lacks the energy to fully manifest itself on any level, is kind of halfway here, halfway there, not fully present anywhere. But that may be prejudicial stereotyping: Maybe I look just as ghostly to them, because of my inability to manifest strongly in their reality. ;)

I've always thought of "poltergeist" as being more a description of the phenomenon--spiritual activity that involves a certain kind of passive-aggressive maliciousness, not real violence or danger but just naughtiness and disruption, or maybe even playful tricksterism--regardless of *what* is causing the activity. The source could be human ghost, inhuman spirit (e.g. fairie), or even the unconscious psychic power of the person who thinks he or she is the "victim" of the poltergeist, but is unwittingly the source of the energy.

From listening to different folks, seems like I hear a lot of people use the terms in roughly this way, but I'll be interested to hear what other people think of these things as being.