Lewis & Short

Pleuron, ōnis, f., = Πλευρών, a city in Ætolia, now Castle of Irene, Plin. 4, 2, 3, § 6; Stat. Th. 2, 727; Ov. M. 7, 382.
Hence, Pleurōnĭus, a, um, adj., = Πλευρώνιος, of or belonging to Pleuron, Pleuronian: Pleuronius Acmon, Ov. M. 14, 494.
Subst.: Pleurōnĭa, ae, f., Ætolia, or that part of Ætolia in which Pleuron is situated, Aus. Epit. 10.