Phanerozoic
[fan-er-uh-zoh-ik]Geology
- the eon comprising the Paleozoic, Mesozoic, and Cenozoic eras.
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- of or relating to this eon.
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Origin of Phanerozoic
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Phanerozoic
- of or relating to that part of geological time represented by rocks in which the evidence of life is abundant, comprising the Palaeozoic, Mesozoic, and Cenozoic eras
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- the Phanerozoic the Phanerozoic era
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Compare Cryptozoic
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Phanerozoic
[făn′ər-ə-zō′ĭk]
- The period of geologic time from about 540 million years ago to the present, including the Paleozoic, Mesozoic, and Cenozoic Eras. When this period of time was first defined, it was thought to coincide with the first appearance of life in the fossil record. It is now known that bacterial and other forms of life were present in the Precambrian Eon, and the Phanerozoic is understood to coincide with the appearance of life forms that evolved external skeletons. See Chart at geologic time.
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The American Heritage® Science Dictionary
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