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Pīraceus (trisyll.) and Pīraeus, i, m., = Πειραιεύς; also Pīraea, ōrum, n. (poet.), the celebrated port of Athens, about five Roman miles from the city, with which it was connected by long walls; the Pirœus, now Porto Dracone or Porto Leone: In Piraeea cum exissem, Cic. Att. 6, 9, 1: venio ad Piraeea: in quo magis reprehendendus sum, quod homo Romanus Piraeea scripserim, non Piraeeum (sic enim omnes nostri locuti sunt), quam in quod addiderim: non enim hoc ut oppido praeposui, sed ut loco … Secutus sum Terentium (Eun. 3, 4, 1): heri aliquot adulescentuli coimus in Piraeeum, Cic. Att. 7, 3, 10: curre in Piraeum, Plaut. Trin. 4, 4, 11: ex Piraeeo abire, Ter. Eun. 2, 2, 59: Piraeeus ille magnificus, Cic. Rep. 3, 32, 44; id. Brut. 13, 51: e litoribus Piraei, Cat. 64, 74: Piraeeus et Phalera portuus, Plin. 4, 7, 11, § 24; Vell. 2, 23, 3.
In neutr.: Sunion expositum Piraeaque tuta recessu Linquit, Ov. F. 4, 563.
Hence, Pīraeus, a, um, adj., of or belonging to the Pirœus, Pirœan: Piraea litora, Ov. M. 6, 446: litus, Sil. 13, 754: portus, Prop. 3 (4), 21, 23.