[1] : The Collaborative International Dictionary of English v.0.48

mishap \mishap"\, n.
   evil accident; ill luck; misfortune; mischance. --chaucer.
   1913 webster

         secure from worldly chances and mishaps. --shak.
   1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

mishap \mishap"\, v. i.
   to happen unluckily; -- used impersonally. obs. "if that me
   mishap." --chaucer.
   1913 webster

[3] : WordNet (r) 2.0

mishap
     n 1: an unpredictable outcome that is unfortunate; "if i didn't
          have bad luck i wouldn't have any luck at all" syn: bad
          luck, mischance
     2: an instance of misfortune syn: misadventure, mischance
see also:
bad luck mischance misadventure 

[4] : Moby Thesaurus II by Grady Ward, 1.0

27 moby thesaurus words for "mishap":
   accident, adversity, blow, calamity, casualty, cataclysm,
   catastrophe, collision, contretemps, crack-up, crash, disaster,
   dole, grief, ill hap, misadventure, mischance, misfortune,
   nasty blow, pileup, shipwreck, shock, smash, smashup,
   staggering blow, tragedy, wreck

[5] : The Free On-line Dictionary of Computing (27 SEP 03)

mishap
     
        early system on ibm 1103 or 1103a.  listed in cacm 25:16,
        may 1959.
     
     

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Mishap, definition of term: Mishap
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