One entry found for tropism.

Main Entry: tro·pism
Pronunciation: tr-piz-m
Function: noun
: an automatic movement by an organism unable to move about from place to place and especially by a plant that involves a turning or growing toward or away from a stimulus (as light or moisture); also : a reflex reaction involving such a movement -- compare TAXIS
- tro·pis·tic /tr-pis-tik/ adjective