The noise a person might make when they are close to shitting themselves. Often made during the run-up to the toilet to signal to others they are
desperate. It is like an
extended "oh no", but very drawn-out to add drama and
excitement to the situation. This noise may be heard throughout the shitting process, and will often be accompanied by vigerous sweating and closed eyes due to severe pain yet a sense of relief.
(Running to the toilet), ooomph! oooooomph! (People move out of the way). (Sitting
on the toilet, with closed eyes). Ooomph! Ooomph! "Dude, can you hear that guy
shitting? He must be
desperate". Oooooooooooomph. (Leaves toilet).