The Collaborative International Dictionary of English v.0.48:

titillation \tit`il*la"tion\ (t[i^]t`[i^]l*l[=a]"sh[u^]n), n.
   [L. titillatio: cf. F. titillation.]
   1. The act of tickling, or the state of being tickled; a
      tickling sensation. --A. Tucker.
      [1913 Webster]

   2. Any pleasurable sensation.
      [1913 Webster]

            Those titillations that reach no higher than the
            senses.                               --Glanvill.
      [1913 Webster]

WordNet (r) 3.0 (2006):

titillation
    n 1: a tingling feeling of excitement (as from teasing or
         tickling)
    2: an agreeable arousal
    3: the act of tickling [syn: tickle, tickling,
       titillation]