E·di·a·ca·ran 
(ē′dē-äkə-rən)
(ē′dē-äkə-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.]