Lewis Short
(adjective) : Firmum, i, n.
* A fortified sea-port of Picenum, now Fermo, Mel. 2, 4, 6; Vell. 1, 14, 8; Pompei. ap. Cic. Att. 8, 12, B. 1.
* Deriv.: Firmānus, a, um, , of or belonging to Firmum, Firmian: cohors,Liv. 44, 40: L. Tarutius Firmanus,of Firmum,Cic. Div. 2, 47, 98: audivi ex Gavio hoc Firmano,id. Att. 4, 8, b, 3: fratres,id. ib.— Subst.: Firmāni, ōrum, m., the inhabitants of Firmum, Firmians, Cic. Phil. 7, 9, 23.—Castellum Firmānōrum, the port of Firmum, regarded as a separate place, now Porto di Fermo, Plin. 3, 13, 18, § 111.
Charlton T. Lewis, Charles Short, A Latin Dictionary