Lewis & Short

Longīnus, i, m. [longus],

  1. I. a Roman surname in the gens Cassia.
    So, Cassius Longinus, v. Cassius.
  2. II. A Grecian philosopher, minister of Zenobia, who was put to death by Aurelian, Vop. Aur. 30; Hier. Ep. 95.