psychopathic

Psychopathic is a very strong word — it means mentally ill or insane and probably dangerous.

Psychopathic isn't a word anyone should take lightly. It refers to an undiagnosed mental disorder. Murderers and other dangerous people are often psychopathic. If you watch a TV show that features a character who is dangerous or even deadly, he might be psychopathic. This is a medical word, unlike "crazy," which can mean dozens of things. If you know that someone is psychopathic, stay away: that person is mentally ill and could hurt you.

Definitions of psychopathic
1

adj suffering from an undiagnosed mental disorder

Synonyms:
psychopathologic, psychopathological
insane
afflicted with or characteristic of mental derangement

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