Lewis & Short

immŏlātĭo (inm-), ōnis, f. [immolo],

  1. I. a sacrificing, a sacrifice (rare but class.): in ipso immolationis tempore, Cic. Div. 1, 52, 119: in ipsa, id. ib. 2, 16, 37: Iphigeniae, Quint. 2, 13, 13.
    In plur.: nefandae, Tac. A. 3, 13.
  2. II. Concr., a sacrifice, offering, Aug. Ep. 36, 30.