Lewis & Short

septemvĭrālis, e, adj. [septemviri], of or belonging to the septemvirs, septemviral: auctoritas, Cic. Phil. 12, 9, 23.
Subst.: septemvĭrāles, ĭum, m., the septemvirs, Cic. Phil. 13, 12, 26.