Skip to Content
Medical Term:


Pronunciation: rod


  1. A slender cylindric structure or device.
  2. The photosensitive, outward-directed process of a rhodopsin-containing rod cell in the external granular layer of the retina; many millions of such rods, together with the cones, form the photoreceptive layer of rods and cones.

Synonym(s): rod cell of retina

[A.S. rod]

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