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Publius, ĭi, m., a Roman prœnomen; in writing, abbrev. P.; e. g. P. Lentulus, to whom are addressed the letters, Cic. Fam. 1, 1 sqq.; v. also Publilius, III.
Hence, Publĭānus, a, um, adj., of or belonging to a Publius: sententia, i. e. of Publius Syrus, Sen. Contr. 7, 18, 8 (where the better reading is Publilianae).