adj. 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. n. The Phanerozoic Eon. [Greek phaneros, visible (from phainein, to cause to appear; see bhā-1 in the Appendix of Indo-European roots) + -ZOIC.] |
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