Pre·cam·bri·an (prē-kămbrē-ən, -kām-)
Of, relating to, or being the geologic time period between Hadean Time and the Cambrian Period, often subdivided into the Archean and Proterozoic Eras, comprising most of the earth's history and marked by the appearance of primitive forms of life. See Table at geologic time.
The Precambrian Eon.
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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:
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