2. Marcus, i, m., a Roman prænomen, in gen. represented by M. simply, e. g. M. Terentius Varro, M. Tullius Cicero; written in full, MAARCVS, Inscr. Rein. 1006; MARCVS, Inscr. Fabr. p. 324, 450; p. 342, 528 et saep. Afterwards also a surname, e. g. C. PONTIVS C. L. MARCVS, Inscr. Grut. 986, 5.
Hence, Marcĭānus, a, um, adj., pertaining to Marcus, Marcian: sodales, the priests who performed the sacred rites instituted in honor of the emperor Marcus Aurelius, Capitol. Pertinax, 15; cf. Spart. Sever. 7; Inscr. Grut. 379.