When you have a turd so big it breaks in two when you flush it down the toilet.
Damn, I just sank the titanic. Turd was so big it broke in two when I flushed it!
When you have been for a shit and the turd is that massive when you flush it, it would sink the titanic
I wouldn't use that bathroom, I just sank the titanic
When you have really big poo and it makes an incredibly loud noise as it hits the water and gives your arse a good splash.
Derives from tragic accident of the Titanic that sank in the mid-atlantic in 1912.
*All quiet*
Rodger - on the toilet: *Loud splash noise*
Christie - in the other room: Jesus, Rodger was that you? Sounded like you sank the Titanic.