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Flexner's bacillus

[flĕks′nərz]
n.
  1. A gram-negative bacterium Shigella flexneri that causes severe dysentery in adults and gastroenteritis in infants.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.