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Eozoic

American  
[ee-uh-zoh-ik] / ˌi əˈzoʊ ɪk /

adjective

Geology.
  1. (formerly) noting or pertaining to the Precambrian Era, especially the period including the beginnings of animal life.


Eozoic British  
/ ˌiːəʊˈzəʊɪk /

adjective

  1. archaic of or formed in the part of the Precambrian era, during which life first appeared

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of Eozoic

First recorded in 1875–80; eo- + zo- + -ic

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

It includes an Azoic age, previous to the appearance of life, and an Eozoic age, including the earliest forms of life. µ This is equivalent to the formerly accepted term Azoic, and to the Eozoic of Dawson.

From Project Gutenberg

I know that if one walks far enough past the Library, in the direction in which the lady with the black ball is looking, one will eventually come to Commonwealth Avenue, where eozoic cabbies may be seen.

From Project Gutenberg

These facts at least allow us to suppose that in the Eozoic times there were great supplies of carbon and of lime available to such creatures of low organisation as were capable of profiting by them; and we have no reason to doubt that there may have been plants and animals so constituted as to flourish in conditions of this kind, in which perhaps scarcely any modern species could exist.

From Project Gutenberg

Certain it is, that according to present appearances we have a new beginning in the Cambrian, which introduces the great Palæozoic age, and few links of connection are known between this and the previous Eozoic.

From Project Gutenberg

At the beginning of the Palæozoic we have reason to believe that our continents were slowly subsiding under the sea, after a period of general continental elevation which was consequent on the crumbling of the earth’s crust at the close of the Eozoic; and on the new sea-bottoms formed by this subsidence came in, slowly at first, but in ever-increasing swarms, the abundant and varied life of the early Palæozoic.

From Project Gutenberg