upper decker

English

Etymology

From upper +‎ deck +‎ -er.

Noun

upper decker (plural upper deckers)

1. (slang) The prank of defecating in the cistern of a toilet, so that flushing the toilet brings in dirty water instead of clean.
   • 2014, John Waters, Role Models:

     Had he been doing “upper deckers” for years in his community?

   • 2017, Molly E. Lee, Love in the Friend Zone:

     Should've bet on him doing an upper decker.