The Collaborative International Dictionary of English v.0.48:

Ictic \Ic"tic\, a. [L. ictus blow.]
   Pertaining to, or caused by, a blow; sudden; abrupt. [R.]
   --H. Bushnell.
   [1913 Webster]

WordNet (r) 3.0 (2006):

ictic
    adj 1: of or relating to a seizure or convulsion [syn: ictal,
           ictic]