Of, relating to, or being the geologic time period from approximately 542 million years ago to the present, comprising the Paleozoic, Mesozoic, and Cenozoic Eras, and marked by an abundance of fossil evidence of life, especially higher forms, in the corresponding rocks. See Table at geologic time.
The Phanerozoic Eon.
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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.