Psychopath doesn't have a clinical definition. It's strictly pop-sci bollocks. (EDIT: "psychopath" does not appear as a diagnosis in ICD10 or DSM IV or DSM V. Other disorders have some overlap with the concept of psychopathy, but there isn't any dx that has a clear mapping.)
That's a good thing, because it avoids stigmatising a real diagnosis that's given to a group of people who are already deeply stigmatised.
