Lewis & Short

Hērennĭus, a,

  1. I. the name of a Roman gens, e. g. C. Herennius, to whom the Rhetorica of Cornificius is dedicated: M. Herennius, an orator, Cic. Brut. 45, 166; id. Mur. 17, 36: Herennius Gallus, Tac. H. 4, 13; 19; 26 sq.: Herennius Senecio, a historian under Domitian, id. Agr. 2; 45; a Samnite Herennius, Liv. 9, 1; Flor. 1, 16, 10.
  2. II. Deriv.: Hērennĭānus, a, um, adj., of or belonging to a Herennius, Herennian: coheredes, Cic. Att. 13, 6, 2.