Lewis & Short

Paestum, i, n.,

  1. I. a city of Lucania, formerly called Posidonia, celebrated for its twice-blowing roses, now Pesti: biferique rosaria Paesti, Verg. G. 4, 119; cf. Ov. M. 15, 708; Prop. 5, 5, 61: oppidum Paestum Graecis Posidonia appellatum, Plin. 3, 5, 10, § 71.
    Hence,
  2. II. Paestānus, a, um, adj., of or belonging to Pœstum, Pœstan: sinus, Cic. Att. 16, 6, 1: rosae, Ov. P. 2, 4, 28.
    In plur.: Paestāni, ōrum, m., the Pœstans, Liv. 37, 10.