Lewis & Short

Hirpīni (Irpīni), ōrum, m.,

  1. I. a people of Lower Italy, between Campania, Lucania, and Apulia, Plin. 3, 11, 16, § 99; Liv. 22, 61, 11; 23, 37; 27, 15: in Hirpinis, in the territory of the Hirpini, Cic. Div. 1, 36, 79; Plin. 2, 93, 95, § 208; so, ex Hirpinis, Liv. 22, 13 init.: in Hirpinis, id. 23, 1.
  2. II. Deriv. Hirpīnus (Irp-), a, um, adj., of or belonging to the Hirpini: ager, fundus, Cic. Agr. 3, 2, 8: pubes, Sil. 8, 571.