Lewis & Short

Phĭlădelphīa, ae, f., = Φιλαδέλφεια, an important city of Lydia, now the town and ruins of Allasher, Vulg. Apoc. 1, 11; 3, 7.
Hence, Phĭlădelphēni, ōrum, m., the inhabitants of the city of Philadelphia in Lydia, Philadelphians, Plin. 5, 29, 30, § 111; Tac. A. 2, 47.