different between callousness vs psychopath

English

callous +? -ness

callousness (usually uncountable, plural callousnesses)

From German psychopatisch, from Ancient Greek ???? (psukh?, “soul”) + ????? (páthos, “suffering”).

psychopath (plural psychopaths)

A person with a personality disorder indicated by a pattern of lying, cunning, manipulating, glibness, exploiting, heedlessness, arrogance, delusions of grandeur, sexual promiscuity, low self-control, disregard for morality, lack of acceptance of responsibility, callousness, and lack of empathy and remorse. Such an individual may be especially prone to violent and criminal offenses.
(figuratively) A person with no moral conscience who perpetrates especially gruesome or bizarre violent acts.
A person diagnosed with antisocial or dissocial personality disorder.
(obsolete) A person diagnosed with any mental disorder.

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