2 Geology relating to or denoting the early part of the Carboniferous period in North America, following the Devonian and preceding the Pennsylvanian. This period corresponds to the Lower Carboniferous of Europe and lasted from about 363 to 323 million years ago.
Archaeology relating to or denoting a settled culture of the south-eastern US, dated to about ad 800–1300.
1a native or inhabitant of Mississippi.
2 (the Mississippian) Geology the Mississippian period or the system of rocks deposited during it.