A turd that is submerged in the U-bend of the toilet like the german submarines (U-boats) used to hide beneath the surface of the sea. 9 out of 10 U-bend U-boats are unflushable in the average toilet.
For fucks sake, that U-bend U-boat just won't flush! Pass me the bog brush Dave, it turd bustin' time!
by MSN NINJA April 19, 2009