After eating one or more Taco Bell Double Decker tacos, then after completing all but the final stages of digestion, the act of unleashing said final stage of digestion in the form of an "upper decker".

This act is considered one of the most high forms of retribution and shall be reserved for only the most heinous of enemies.
Jake is a twat! He stole $60 from me and used it to take my ex-girlfriend on a date. While they're out, I'm going to wolf down 8 Double Deckers, break into his house, and leave him a nice smelly London Tour Bus in the top of his toilet.
by Mr. FancyPants July 14, 2014
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