"pertaining to or of the nature of psychopathy," 1847, from psychopathy on model of German psychopatisch, from Greek psykhē "mind" (see psyche) + pathos "suffering" (from PIE root *kwent(h)- "to suffer").

"person with a high degree of empathic ability," by 1980, from empathic, etc. (compare psychopath/psychopathic).

1925 as short for psychologist; (earlier short for psychology, 1921); as short for psychopath by 1942.

"one having a violent anti-social pattern of behavior or mental attitude," 1930, coined or popularized by psychologist George E. Partridge (1870-1953) from socio- on model of psychopath (q.v.) .