Definitions by The can man.

shitload 

A shit load is enough fecal matter to fill a toilet bowl. However, if that load plugs the toilet, it is deemed a shit overload.

Kenny: "Call the plumber! David had a shit overload!"
David: "No, no, it was just a shitload. She went down just fine!"

shitload by The can man. December 2, 2011