The Collaborative International Dictionary of English v.0.48:

Miscarry \Mis*car"ry\, v. i. [imp. & p. p. Miscarried; p. pr.
   & vb. n. Miscarrying.]
   [1913 Webster]
   1. To carry, or go, wrong; to fail of reaching a destination,
      or fail of the intended effect; to be unsuccessful; to
      suffer defeat.
      [1913 Webster]

            My ships have all miscarried.         --Shak.
      [1913 Webster]

            The cardinal's letters to the pope miscarried.
                                                  --Shak.
      [1913 Webster]

   2. To bring forth young before the time they are viable; to
      have a spontaneous abortion.
      [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

miscarry
    v 1: be unsuccessful; "Where do today's public schools fail?";
         "The attempt to rescue the hostages failed miserably" [syn:
         fail, go wrong, miscarry] [ant: bring home the
         bacon, come through, deliver the goods, succeed,
         win]
    2: suffer a miscarriage [ant: carry to term]