Someone who thinks of ways to hurt people and then acts on those thoughts.
To me, it's ALL about intelligence....
It's a vague term with many meanings. It can either mean somebody is insane or at least very odd, perhaps with a dark sense of humour.
Someone that has a sadistic mind or if you mean it literally , someone whose mind looked like a rag being twisted here and there.
It could mean that someone is not sane or "evil".
A mind that does not reach a normal and reasonable conclusion, when processing the facts available to it.
You are somewhat crazy. That's what it means.
It is a medical condition.
I prefer fucktarded myself.