upper decker
Noun
Meaning
upper decker (plural upper deckers)
(slang) The prank of defecating in the cistern of a toilet, so that flushing the toilet brings in dirty water instead of clean.
Noun
upper decker (plural upper deckers)
(slang) The prank of defecating in the cistern of a toilet, so that flushing the toilet brings in dirty water instead of clean.