Lewis & Short

Pompĭlĭus, a, name of a Roman gens. The most celebrated is Numa Pompilius, the second king of Rome, Hor. C. 1, 12, 34; Ov. F. 2, 69; Liv. 1, 18.
Hence,

  1. A. Pom-pĭlĭus, a, um, adj., of or belonging to Pompilius, Pompilian: sanguis, i.e. descendants of Numa Pompilius, Hor. A. P. 292.
  2. B. Pompĭlĭānus, a, um, adj., Pompilian: curia, built by Numa, Vop. Aur. 41: indigitamenta, Arn. 2, 95.