The Collaborative International Dictionary
positive thigmotaxis
Thigmotaxis \Thig`mo*tax"is\, n. [NL., fr. Gr. ? touch + ? an arranging.] (Physiol.) The property possessed by living protoplasm of contracting, and thus moving, when touched by a solid or fluid substance.
Note: When the movement is away from the touching body, it is negative thigmotaxis; when towards it, positive thigmotaxis.