Tropism

In biology, a tropism is a phenomenon indicating the growth or turning movement of an organism, usually a plant, in response to an environmental stimulus.

Tropisms are usually named for the stimulus involved; for example, a phototropism is a movement to the light source, and an anemotropism is the response and adaptation of plants to the wind.

[3] The term "tropism" (from Ancient Greek τρόπος (trópos) 'a turn, way, manner, style, etc.'

In English, the word tropism is also used to indicate an action done without cognitive thought: However, "tropism" in this sense has a proper, although non-scientific, meaning as an innate tendency, natural inclination, or propensity to act in a certain manner towards a certain stimulus.

[4] Both of these are orthotropic,[5] and can be contrasted with tropisms that are diatropic (perpendicular to the stimulus) or plagiotropic (at an oblique angle).