Lewis & Short

Mĕtăpontum, i, n., a town of Lucania, where Pythagoras lived and died, now Torre a Mare, Cic. Fin. 5, 2, 4; Liv. 1, 18, 8; Mela, 2, 4, 3; Plin. 3, 11, 15, § 97.
Hence, Mĕtăpontīnus, a, um, adj., Metapontine: ager, Liv. 24, 20.
In plur.: Mĕtă-pontīni, ōrum, m., the Metapontines, Liv. 22, 61.