Source : Webster's Revised Unabridged Dictionary (1913)

Ticklish \Tic"klish\, a.
   1. Sensible to slight touches; easily tickled; as, the sole
      of the foot is very ticklish; the hardened palm of the
      hand is not ticklish. --Bacon.

   2. Standing so as to be liable to totter and fall at the
      slightest touch; unfixed; easily affected; unstable.

            Can any man with comfort lodge in a condition so
            dismally ticklish?                    --Barrow.

   3. Difficult; nice; critical; as, a ticklish business.

            Surely princes had need, in tender matters and
            ticklish times, to beware what they say. --Bacon.
      -- {Tic"klish*ly}, adv. -- {Tic"klish*ness}, n.