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

mackle \mac"kle\, n. see macle.
   same as macule.
   1913 webster
see also:
macle macule 

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

mackle \mac"kle\, v. t.  i.
   to blur, or be blurred, in printing, as if there were a
   double impression.
   1913 webster

[3] : WordNet (r) 2.0

mackle
     n : a printed impression that is blurred or doubled

Mackle >> M Words
Mackle, definition of term: Mackle
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