diarrhoea

noun

Diarrhoea is referred to flimsy, even liquid poop that causes a tummy ache. When you have diarrhoea, you poo a few times in one day. Thus, you may want to eat boiled rice, chicken and cooked apples as these foods will help you poo normally again. Sometimes the diarrhoea is so bad that you have to visit a doctor.

We can also use stomach flu and more popularly we can use the word the runs.