Lewis & Short

Sămŏthrācĭa, ae, f., Samothrace, an island near the coast of Thrace, famous for the mystic worship of the Cabiri, now Samothraki, Cic. N. D. 1, 42, 119; 3, 37, 87; id. Pis. 36, 89; Varr. L. L. 5, § 58 Müll.; Verg. A. 7, 208.
Also called Sămŏthrācē, ēs, f., Varr. R. R. 2, 1, 5; Mel. 2, 7, 8; Plin. 4, 12, 23, § 73; Sămŏthrāca, ae, f., Liv. 42, 25; 44, 45; 44, 46; and Thrēïcĭa Să-mus or Sămos, after the Gr. θρηϊκίη Σάμος, Verg. A. 7, 208; Ov. Tr. 1, 10, 20.
Hence,

    1. 1. Sămŏthrācĭus, a, um, adj., Samothracian: ferrea (a kind of rings first made there), Lucr. 6, 1044 (cf. Plin. 33, 1, 6, § 23): caepa, Plin. 19, 6, 32, § 101: insula, i. e. Samothrace, and, named from it, gemma, id. 37, 10, 67, § 181 (Jahn, Samothraca).
    2. 2. Sămŏthrāces, um, m., the inhabitants of Samothrace, the Samothracians, Varr. L. L. 5, § 58; Liv. 45, 5; Curt. 8, 1, 25; Stat. Achill. 2, 157.
      Also a dject.: Samothraces di, the Cabiri, Varr. 1. 1.; Macr. S. 3, 4; also absol.: jures licet et Samothracum Et nostrorum aras, Juv. 3, 144.
    3. 3. Sămŏthrācēnus, a, um, adj., Samothracian: Zocles, of Samothrace, Plin. 11, 37, 63, § 167.
    4. 4. Sămŏthrācĭcus, a, um, adj., Samothracian: religiones, Macr. S. 3, 4.
    5. 5. Sămŏthrācus, a, um, adj., Samothracian: vates, Val. Fl. 2, 439.