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E·di·a·ca·ran

(ē′dē-äkə-rən)

adj.

1. Of or relating to the final geologic period of the late Precambrian Era, lasting from 620 to 542 million years ago.

2. Of or relating to a group of fossilized soft-bodied marine organisms that are the earliest known remains of multicellular life and date from between 560 and 542 million years ago.

[After the Ediacaran Hills in southern Australia, where the first such fossils were found.]

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:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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