(1):

(a.) Sensible to slight touches; easily tickled; as, the sole of the foot is very ticklish; the hardened palm of the hand is not ticklish.

(2):

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

(3):

(a.) Difficult; nice; critical; as, a ticklish business.