light reflex(redirected from fundus reflex)
Also found in: Dictionary, Thesaurus, Medical.
light reflex[′līt ‚rē‚fleks]
The postural orientation response of certain aquatic forms stimulated by the source of light; receptors may be on the ventral or dorsal surface.
The response in which the pupil dilates when light levels are lowered, and constricts when light levels are raised.