Skip to Content
Medical Term:


Pronunciation: fo'to-tak'sis

Definition: Reaction of living protoplasm to the stimulus of light, involving bodily motion of the whole organism toward (positive phototaxis) or away from (negative phototaxis) the stimulus.

[photo- + G. taxis, orderly arrangement]

© Copyright 2016 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.