a. [ L. Apenninus, fr. Celtic pen, or ben, peak, mountain. ] Of, pertaining to, or designating, the Apennines, a chain of mountains extending through Italy. [ 1913 Webster ]
a. (Zool.) Of or pertaining to the Longipennes; longipennate. [ 1913 Webster ]
a. [ L. penna feather + E. nerve. ] Pinnately veined or nerved. [ 1913 Webster ]
a. Under, or at the foot of, the Apennine mountains; -- applied, in geology, to a series of Tertiary strata of the older Pliocene period. [ 1913 Webster ]