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definitions

rose bengal

[rōz′ bĕn-gôl′, bĕng-, bĕn′gəl, bĕng′-]
n.
  1. A bluish-red dye used as a stain for bacteria, as a stain in the diagnosis of keratitis sicca, and in tests of liver function.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.