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Pronunciation: kon


  1. A surface joining a circle to a point above the plane containing the circle.
  2. The photosensitive, outward-directed, conic process of a cone cell essential for sharp vision and color vision; cones are the only photoreceptors in the fovea centralis and become interspersed with increasing numbers of rods toward the periphery of the retina.
  3. Metallic cylinder or truncated cone, either circular or square in cross-section, used to confine a beam of x-rays.

Synonym(s): cone cell of retina

[G. konos, cone]

Further information

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.