The story
Derived from the Autun Basin, where the first geological rock layers originating from this period were found and studied.https://www.sciencedirect.com/science/article/pii/S0031018225006091
Etymology from Wiktionary, CC BY-SA 4.0.
Autunian
Today it means: An age from ~300 to ~275 million years ago, a subdivision of the Carboniferous-Permian. Full definition →