Pennīnus

I. the latter orthog. on account of the false derivation from Poeni, because Hannibal marched over this mountain to Italy, Liv. 21, 38, 6 sqq.; Plin. 3, 17, 21, § 123), a, um, adj. from the Celtic Pen or Penn, summit, peak, of or belonging to the Pennine Alps (between the Valais and Upper Italy, the highest point of which is the Great St. Bernard), Pennine: Alpes, Plin. 3, 17, 21, § 123; Tac. H. 1, 87; called also, juga, id. ib. 1, 61: mons, Sen. Ep. 31, 9; also, absol.: Penninus, Liv. 5, 35; 21, 38: iter, Tac. H. 1, 70: VALLIS POENIN, Inscr. Grut. 376, 6: DEO PENINO D. D., the local deity of the Pennine Alps, Inscr. Spon. Misc. Ant. p. 85, n. 30; called also, IVPPITER POENINVS, and simply, POENINVS, Inscr. Orell. 228 sq.
Lewis & Short
A Latin Dictionary, 1879
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