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Cōpōnĭus, a, the name of a plebeian family at Rome, e. g. the two brothers, T. and C. Coponii, Cic. Cael. 10, 24; id. Balb. 23, 53.
Hence, Cōpōnĭānus, a, um, adj., of or pertaining to Coponius, Cic. Att. 12, 31, 2.