Lewis & Short

īsĕlastĭcus, a, um, = εἰσελαστικός,

  1. I. of or belonging to a public entrance: certamen or agon, a public contest, the victors in which were conducted home in triumphal procession, Plin. Ep. 10, 119 init.; so, ludi, Suet. Calig. 20; Vitr. praef. 9.
  2. II. Subst.: īsĕlastĭcum, i, n., the reward presented to such a victor by the emperor, Trajan. ap. Plin. Ep. 10, 120.