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).
Pennus, i, m., a Roman surname : T. Quinctius Pennus, Liv. 4, 26. ...
A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.