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psy·chop·a·thy (sī-kŏpə-thē)
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n.
1. A personality disorder characterized by deceitfulness, manipulation, grandiosity, lack of empathy or guilt, and often aggressive or violent behavior. It is sometimes considered a subset of antisocial personality disorder.
2. Mental illness. No longer in clinical use.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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