Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Tĕrīna, ae, f., a town in the Bruttian territory, Plin. 3, 5, 10, § 72; Liv. 8, 24.
Hence, Tĕrīnaeus, a, um, adj., of or belonging to Terina: sinus, the Gulf of Santa Eufemia, Plin. 3, 5, 10, § 72: Elysius, Cic. Tusc. 1, 48, 115.