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aztreonam

[ăz-trē′ə-năm′]
n.
  1. A synthetic bactericidal antibiotic that acts against a wide spectrum of gram-negative aerobic pathogens.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.