thig·mot·ro·pism 
(thĭg-mŏtrə-pĭz′əm)
(thĭg-mŏtrə-pĭz′əm)n.
The movement or growth of an organism in a particular direction in response to contact with a solid object.
[Greek thigma, touch; see THIGMOTAXIS + -TROPISM.]
thig′mo·tropic (thĭg′mə-trōpĭk) adj.