an apparatus used in plant physiology experiments to eliminate the one-sided influence of certain environmental factors, primarily gravity and light; first employed by the German botanist J. Sachs (in the 1880’s).
A plant attached to the revolving axis of the apparatus will continue to grow in its original direction, because the slow revolution of the axis while not eliminating the action of gravity, does prevent it from acting one-sidedly. A clinostat can be used, for example, to eliminate the phototropic deflections caused by onesided light or to study the time it takes for a plant to react to various stimuli.