misbug

from Jargon File (4.4.4, 14 Aug 2003)
misbug
 /mis.buhg/, n.

   [MIT; rare (like its referent)] An unintended property of a program
   that turns out to be useful; something that should have been a {bug}
   but turns out to be a {feature}. Compare {green lightning}. See
   {miswart}.
    
from The Free On-line Dictionary of Computing (8 July 2008)
misbug

   /mis-buhg/ [MIT] An unintended property of a program that
   turns out to be useful; something that should have been a
   {bug} but turns out to be a {feature}.  Usage: rare.  Compare
   {green lightning}.  See {miswart}.

   [{Jargon File}]
    

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