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.
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
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