Brown Iceberg
This is a special case of a Big Kahuna, itself a large turd. When any portion of the turd sticks above the waterline, you have created a Brown Iceberg. Much like it's icy namesake, the vast majority of the Brown Iceberg lies below the surface. When turds have achieved this dangerous size, it will often not flush down the toilet, resulting in a Pooplug.
I ate 2 pounds of Mexican food last night and found a brown iceberg in the toilet shortly thereafter!
Brown Iceberg
Shitting in someones mouth and leaving a small peak sticking out of the mouth so 80% is below the surface and 20% is visible.
He had such a large brown iceberg rammed in his mouth.