The story
Named after the Belgian city of Tournai.
Etymology from Wiktionary, CC BY-SA 4.0.
Tournaisian
Today it means: In the ICS geologic timescale, the lowest stage or oldest age of the Mississippian, the oldest subsystem of the Carboniferous. It lasted from 358.9 Ma to 346.7 Ma and was preceded by the Famennian and followed by the Viséan. Full definition →