The Collaborative International Dictionary of English v.0.48:

Psychopathy \Psy*chop"a*thy\, n. [Psycho- + Gr. ?, ?.] (Med.)
   Mental disease. See Psychosis, 2. -- Psy`cho*path"ic, a.
   -- Psy*chop"a*thist, n.
   [1913 Webster]

WordNet (r) 3.0 (2006):

psychopathy
    n 1: any disease of the mind; the psychological state of someone
         who has emotional or behavioral problems serious enough to
         require psychiatric intervention [syn: mental illness,
         mental disease, psychopathy] [ant: mental health]

Moby Thesaurus II by Grady Ward, 1.0:

42 Moby Thesaurus words for "psychopathy":
   aberration, abulia, alienation, arteriosclerotic psychosis,
   certifiability, character disorder, dementia paralytica,
   derangement, dipsomania, distraction, drug addiction,
   folie du doute, functional psychosis, general paralysis,
   general paresis, insaneness, lunacy, madness, metabolic psychosis,
   moral insanity, neurosis, organic psychosis, paralytic dementia,
   pathological drunkenness, personality disorder, presenile dementia,
   prison psychosis, psychopathia, psychopathia sexualis,
   psychopathic condition, psychopathic personality, psychosis,
   senile dementia, senile psychosis, senility, sexual pathology,
   sexual psychopathy, situational psychosis, sociopathy,
   syphilitic paresis, toxic psychosis, unbalance