In Norse mythology, the apocalyptic battle that the gods will fight against the giants before the world perishes in flame and is created anew.
[Old Icelandic Ragnarökkr, Ragnarök : ragna, genitive pl. of regin, the gods (pl.) + rökr, rökkr, twilight or rök, reason, origin, marvel (perhaps originally "twilight of the dawn, rebirth" ); both akin to Old Icelandic rökva, rökkva, to grow dark, and Greek Erebos, Erebus.]
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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.