psy·cho·pa·thol·o·gy (sī′kō-pə-thŏlə-jē, -pă-)
1. The study of the origin, development, and manifestations of mental or behavioral disorders.
2. The manifestation of a mental or behavioral disorder.
psy′cho·path′o·logic (-păth′ə-lŏjĭk), psy′cho·path′o·logi·cal (-ĭ-kəl) adj.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 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:
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