The Collaborative International Dictionary of English v.0.48:

Tickle \Tic"kle\, v. t. [imp. & p. p. Tickled; p. pr. & vb. n.
   Tickling.] [Perhaps freq. of tick to beat; pat; but cf.
   also AS. citelian to tickle, D. kittelen, G. kitzlen, OHG.
   chizzil[=o]n, chuzzil[=o]n, Icel. kitla. Cf. Kittle, v. t.]
   1. To touch lightly, so as to produce a peculiar thrilling
      sensation, which commonly causes laughter, and a kind of
      spasm which become dangerous if too long protracted.
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            If you tickle us, do we not laugh?    --Shak.
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   2. To please; to gratify; to make joyous.
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            Pleased with a rattle, tickled with a straw. --Pope.
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            Such a nature
            Tickled with good success, disdains the shadow
            Which he treads on at noon.           --Shak.
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Moby Thesaurus II by Grady Ward, 1.0:

42 Moby Thesaurus words for "tickled":
   amused, attracted, cathectic, charmed, comfortable, concerned,
   content, contented, cozy, curious, delighted, diverted, easy,
   entertained, enthusiastic, eupeptic, euphoric, excited,
   exhilarated, fascinated, favorably impressed with, glad, gladsome,
   gratified, in clover, interested, intrigued, keen on, passionate,
   piqued, pleased, pleased as Punch, pleased with, satisfied,
   sold on, taken with, tantalized, thrilled, tickled pink,
   tickled to death, titillated, turned-on