Steatorrhea means excess undigested fat in feces. In this case, the feces is often lighter, sometimes whitish, in color. It produces a fouler-than-usual, sour-rancid smell, and floats on the surface of the water as opposed to sinking to the bottom of the toilet bowl.
Research should be done, and a doctor consulted if necessary, to determine the cause of the inability to digest and absorb fat.
The causes range from mild to very severe and life-threatenting, so simply treating symptoms may not be enough.