Shit dust, dried poop that has become a type of shit dust or Shust.
Fine particles of poo (as in dried poop)
The particles into which poop disintegrate
a : a cloud of Shust
His underwear was covered with shust.
You can see the shust particles floating through the air after a fart on a dry day.
A cloud of shust
After a good cleaning there isn't a sign of any shust on that anus
He developed pink-eye after having shust in his eye.
I shusted his drink in revenge for sleeping with my sister.