Steatorrhea (or steatorrhoea) is the presence of excess fat in feces. Stools may also float due to excess gas, have an oily appearance and can be especially foul-smelling. An oily anal leakage or some level of fecal incontinence may occur. There is increased fat excretion, which can be measured by determining the fecal fat level. The definition of how much fecal fat constitutes steatorrhea has not been standardized.