Lewis and Short

Sĕrāpis (a short, Prud. adv. Symm. 2, 531; Mart. Cap. 2, § 191; Paul. Nol. Carm. 26, 100), is and ĭdis, m., = Σάρᾶπις, a chief divinity of the Egyptians, subsequently worshipped also in Greece and Rome, Varr. L. L. 5, § 57 Müll.; id. ap. Aug. Civ. Dei, 18, 5; Macr. S. 1, 20 fin.; Cic. Div. 2, 59, 123; id. N. D. 3, 19, 47; id. Verr. 2, 2, 66, § 160; Varr. ap. Charis. p. 69 P.; Plin. 37, 5, 19, § 75; Tac. H. 4, 81; 4, 84; Suet. Vesp. 7; Spart. Sev. 17; Mart. 9, 30, 6; Inscr. Orell. 931; 950; 987; 1887 sq.
Hence,

A. Sĕ-rāpēum, i, n., a temple of Serapis, the most celebrated in Alexandria, Tert. Apol. 18 fin.; id. Spect. 8 fin.; Lampr. Alex. Sev. 27; Amm. 22, 16, 12; cf. Tac. H. 4, 84.
B. Sĕrāpĭcus, a, um, adj., of or belonging to Serapis, Serapian; transf., splendid, sumptuous: cenae, Tert. Apol. 39 med.

Lewis & Short