In Germanic folklore, a spirit or creature that dwells in the forest and captures people, carrying them off to their deaths.
[Partial translation of German Erlkönig, alteration and partial translation of earlier Danish elverkonge, ellekonge, elf-king (taken by Johann Gottfried von Herder in his translation of a Danish ballad as "alder-king," influenced by German Erle, alder, since the alder is associated with the supernatural in Germanic myth and folklore) : elv, elf; see albho- in the Appendix of Indo-European roots + konge, king.]
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Indo-European & Semitic Roots Appendicies
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.