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Phleg·e·thon

(flĕgə-thŏn′)

n.
Greek Mythology

A river of fire, one of the five rivers of Hades.

[Middle English Flegeton, from Latin Phlegethōn, from Greek, from present participle of phlegethein, to blaze, variant of phlegein; see bhel-¹ in the Appendix of Indo-European roots.]

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:

Indo-European Roots

Semitic Roots

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.

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