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antithrombin

noun
  1. biochem a substance that counteracts the action of thrombin, preventing the formation of blood clots
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
antithrombin in Medicine

antithrombin

[ăn′tē-thrŏm′bĭn, ăn′tī-]
n.
  1. An anticoagulant that inhibits or prevents the effects of thrombin.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.