1. The earliest epoch in the Pennsylvanian, comprising the Kinderscoutian, Marsdenian, and Yeadonian ages (these are also stage names in British stratigraphy), and the Cheremshanskian and Melekesskian ages (stage names in Russian stratigraphy). The Bashkirian age is preceded by the Serpukhovian, followed by the Moscovian, and has its initial boundary (the Mississippian–Pennsylvanian boundary) dated at 318.1 Ma ago and its end at 311.7 Ma ago (Int. Commission on Stratigraphy, 2004).

2. The name of the corresponding eastern European series, which is roughly contemporaneous with the Namurian B and C plus the Westphalian A (western Europe), and the Morrowan series (N. America).