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

muggins \mug"gins\, v. t.
   in certain games, to score against, or take an advantage over
   an opponent, as for an error, announcing the act by saying
   "muggins."
   webster 1913 suppl.

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

muggins \mug"gins\, n. etym. unknown.
   1. a game of dominoes in which the object is to make the sum
      of the two ends of the line some multiple of five.
      webster 1913 suppl.

   2. a game at cards which depends upon building in suits or
      matching exposed cards, the object being to get rid of
      one's cards.
      webster 1913 suppl.

[3] : WordNet (r) 2.0

muggins
     n : a person who lacks good judgment syn: fool, sap, saphead,
          tomfool
see also:
fool sap saphead tomfool 

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