Of, relating to, or being the period of geologic time from about 416 to 359 million years ago, the fourth period of the Paleozoic Era. The Devonian Period is characterized by the development of lobe-finned fishes, the appearance of amphibians and insects, and the first forests. See Table at geologic time.
The Devonian Period.
[After Devon, a county of southwest England.]
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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.