malignant \ma*lig"nant\, a. [L. malignans, -antis, p. pr.
         of
   malignare, malignari, to do or make maliciously.
         See
   Malign, and cf.
         Benignant.]
   1.
         Disposed to do harm, inflict suffering,
         or cause distress;
      actuated by extreme malevolence or
         enmity; virulently
      inimical; bent on evil;
         malicious.
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            A malignant and a turbaned Turk.      --Shak.
     
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   2. Characterized or caused by evil
         intentions; pernicious.
      "Malignant care."
         --Macaulay.
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            Some malignant power upon my life.    --Shak.
     
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            Something deleterious and malignant as his touch.
                                                  --Hawthorne.
     
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   3. (Med.) Tending to produce death;
         threatening a fatal
      issue; virulent; as, malignant
         diphtheria.
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   Malignant pustule
         (Med.), a very contagious disease
      produced by
         infection of subcutaneous tissues with the
      bacterium
         Bacillus
         anthracis. It is transmitted to man
      from
         animals and is characterized by the formation, at the
     
         point of reception of the infection, of a vesicle or
     
         pustule which first enlarges and then breaks down into an
 
             unhealthy ulcer. It is marked by profound exhaustion
         and
      often fatal. The disease in animals is called
         charbon;
      in man
         it is called cutaneous anthrax,
         and formerly was
      sometimes called simply anthrax.

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