I once asked a similar question about Jason Voorhees. Turns out the closest equivalent for Jason is a Revenant btw.
As for Freddy I think the most appropriate term may be Fiend.
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Ghosts can possess. Fred has a human origin. Don't think demons have human origins.
ᴳᵒ ᶠᵘᶜᵏ ʸᵒᵘʳˢᵉˡᶠ

an evil spirit or devil, especially one thought to possess a person or act as a tormentor in hell.
Freddy possessed that guy in ANOES Part 2

How is he a demon?
ᴳᵒ ᶠᵘᶜᵏ ʸᵒᵘʳˢᵉˡᶠ

He's a demon. Just because a movie had to be made after the fact in order to spoon fed to stupid people what they should already have realized.

In New Nightmare, but not even in Freddy's Dead, he is a demon. He is given powers by dream demons, but he is not one. Just a ****ed up bastard of a nun raped by a psycho. Died, and came back through dreams.
ᴳᵒ ᶠᵘᶜᵏ ʸᵒᵘʳˢᵉˡᶠ

Freddy is a demon

That's nice.
ᴳᵒ ᶠᵘᶜᵏ ʸᵒᵘʳˢᵉˡᶠ

I wouldn't consider him anything. I'm not 9 years old and I have a job.
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how about dream ghost? sounds better in german
@christina
traum das gespenst
yes he's in their dreams, but i wish the writer had given him the power to assume physical form along with his mental presence so then freddy would have been a major force to deal with

I know it gets more complicated with Freddy's Dead, but like looking at the first movie only, he's a dead guy that comes back as a spirit. You just usually don't get spirits limited to dreams. He definitely falls under the definition of ghost, but also something more unique. But it's funny how you never see him referred to as a ghost.
I mean, Beetlejuice isn't a traditional ghost, but we still refer to him as a ghost. Does help that he calls himself the ghost with the most.
ᴳᵒ ᶠᵘᶜᵏ ʸᵒᵘʳˢᵉˡᶠ

A ghost turned into a demonesque being.
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