What is the name given to a plant's growth response to touch?

Thigmotropism is the term used to describe a plant's growth response to touch or mechanical stimulation. This response is especially evident in climbing plants like vines, which use contact with structures to support their growth. When these plants encounter an object or surface, specific cells respond to the touch by promoting growth on one side and inhibiting it on the other. This results in the plant winding around or climbing the object.

The other terms refer to different types of growth responses: chemotropism involves growth in response to chemical signals, hydrotropism is the growth response toward or away from water, and geotropism involves growth in response to gravity. Each of these responses is distinct and serves different adaptive functions in the plant's growth and development.