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‡ 1. pennus, a, um, adj. [pinna], pointed, sharp: pennum antiqui acutum dicebant: unde et avium pennae, quia acutae, Isid. Orig. 19, 19, 11 dub. (al. pinnum).
2. Pennus, i, m., a Roman surname: T. Quinctius Pennus, Liv. 4, 26.