a. A state of emotional and psychological well-being in which one is able to use one's cognitive and emotional capabilities, function in society, and meet the ordinary demands of everyday life.
b. A person's overall emotional and psychological condition: Since witnessing the accident, his mental health has been poor.
2. A field comprising various professions, such as psychiatry and social work, that deals with the prevention, diagnosis, and treatment of mental disorders.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 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:
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.