Pillow top is a group of immature teenage boys who think they're cool and a transetter but in reality they really just don't know how to be a decent person and could care less about anyone about anyone. They're shady and shitty, and will more than likely cheat on you.
The effect that occurs when a woman wears a bra that's a cup or two too small for her thus forcing her boobs to pillow above the edge of the cup creating deeper cleavage than normal.
A set of abdominal muscles, well-developed but hidden by a layer of fat 3/8 to 1/2 inch thick, just enough to hide the six-pack. May progress into Dunlap Disease, depending on eating habits and level of physical activity of the owner.
Hey Joe, if you're gonna compete in that bodybuilding contest, ya gotta lose the pillow top six-pack!