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Cen·o·zo·ic

(sĕn′ə-zōĭk, sē′nə-)

adj.

Of, relating to, or being the most recent era of geologic time, from about 66 million years ago to the present. The Cenozoic Era includes the Tertiary Period and the Quaternary Period and is characterized by the formation of modern continents, glaciation, and the diversification of mammals, birds, and plants. See Table at geologic time.

The Cenozoic Era.

[Greek kainos, new; see ken- in the Appendix of Indo-European roots + -ZOIC.]

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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