Psychopath (noun)

1. A person suffering from a chronic mental disorder with abnormal or violent social behavior.
2. A person with a personality disorder characterized by a pervasive pattern of disregard for, or violation of, the rights of others.

Origin:

From psych- ("mind") + -path ("suffering"), coined by psychiatrist benjamin rush in 1835.

Examples:

1. The serial killer was diagnosed as a psychopath who felt no remorse for his actions.
2. The psychopath's lack of empathy made it impossible for him to form close relationships.
3. He was considered a dangerous psychopath who could not be trusted.
4. The study of psychopathy is an important area of research in the field of criminal psychology.
5. Psychopaths are often portrayed as charming and intelligent, but lacking in empathy and remorse.