fre·net·ic or phre·net·ic (frə-nĕtĭk) also fre·net·i·cal or phre·net·i·cal (-ĭ-kəl)
Wildly excited or active; frantic; frenzied.
[Middle English frenetik, from Old French frenetique, from Latin phrenēticus, from Greek phrenītikos, from phrenītis, brain disease, from phrēn, mind; see gwhren- in the Appendix of Indo-European roots.]
fre·neti·cism (-ĭ-sĭz′əm) n.
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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.