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arcus cornealis

[kôr′nē-ā′lĭs]
n.
  1. An opaque, grayish ring at the periphery of the cornea just within the sclerocorneal junction, common among the elderly and resulting from a deposit of fatty granules in, or hyaline degeneration of, the lamellae and cells of the cornea.anterior embryotoxon arcus adiposus arcus juvenilis arcus senilis gerontoxon
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.