Permian (Per'-mi-an). The uppermost system of the Paleozoic Erathem of the Standard Global Chronostratigraphic Scale, above the Carboniferous and below the Triassic System of the Mesozoic Erathem. Also the time during which these rocks were formed, the Permian Period, covering the time span between 295 and 250 Ma. It is named after the province of Perm, Russia, where rocks of this age were first studied.