The erection you receive while excreting feces from your anus.

Also can be Shitboner or Shitbonér if you're French.

Gay guys erection.

When one suffers from the adverse side-effects (mostly bowel related) of Viagra.

a euphemism for premature ejacluation that is used when someone fucks up

When you are taking a shit and the shit won't fall down and it is really hard and all