noting or pertaining to the earliest era of earth history, ending 570 million years ago, during which the earth's crust formed and life first appeared in the seas.
the Precambrian Era.
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How to use Precambrian in a sentence
We may take our own country as a region where a good development of the Precambrian rocks occurs.
A few explanatory remarks concerning the mode of detection of Precambrian rocks may not be amiss.
These Torridonian strata furnish us with the most satisfactory group of Precambrian sediments yet detected in Britain.
British Dictionary definitions for Precambrian
of, denoting, or formed in the earliest geological era, which lasted for about 4 000 000 000 years before the Cambrian period
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
Scientific definitions for Precambrian
The period of geologic time between Hadean Time and the Phanerozoic Eon, from about 3.8 billion to 540 million years ago. During the Precambrian Eon, which is divided into the Archean and Proterozoic, primitive forms of life first appeared on Earth. See Chart at geologic time.
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