I mean, I’m not the absolute expert here, but we would likely identify it as something other than chyme. Diarrhoea (I like the british spelling because, as someone else put it, it looks like you’ve lost control of your vowels) isn’t chyme, nor really feces. There’s sort of a hierarchy of naming things, right, so what they are most is what we call them, so it would just be called diarrhoea.