Contraindication

from WordNet (r) 3.0 (2006)

contraindication
    n 1: (medicine) a reason that makes it inadvisable to prescribe
         a particular drug or employ a particular procedure or
         treatment [ant: {indication}]

from The Collaborative International Dictionary of English v.0.48

Contraindication \Con"tra*in`di*ca"tion\, n. (med.)
   An indication or symptom which forbids the method of
   treatment usual in such cases.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

28 Moby Thesaurus words for "contraindication":
      antagonism, antipathy, antithesis, clashing, collision, conflict,
      confrontation, contradiction, contradistinction, contraposition,
      contrariety, contrast, counterposition, cross-purposes,
      disagreement, discrepancy, hostility, inconsistency, inimicalness,
      oppositeness, opposition, opposure, oppugnance, oppugnancy,
      perversity, polarity, repugnance, showdown

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