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diph·y·cer·cal

(dĭf′ĭ-sûrkəl)

adj.

Having or designating a tail fin in which the vertebral column extends to the tip, with symmetrical upper and lower parts, as in the lungfishes.

[Greek diphuēs, double; see DIPHYODONT + kerkos, tail + -AL¹.]

diph·y·cercy (-sûrsē) n.

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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