ma·ni·a·cal (mə-nīə-kəl) also ma·ni·ac (mānē-ăk′)
1. Suggestive of or afflicted with extreme mental derangement: a maniacal frenzy.
2. Characterized by excessive enthusiasm or excitement: a maniacal interest in gambling.
3. Wildly irresponsible: maniacal drivers.
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:
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