Snake's Belly 

Part of the Australian phrase "Lower than a snake's belly", signifying that the stomach of a snake would be particularly low to the ground. This term is used to desribe an act committed by a person which was low, or a low person in general.

"So when her husband was away she slept with the husband's brother"

"Damn, that woman is the snake's belly, I tell you."

Snake's Belly by funkie_chick87 September 21, 2005

lower than a snake's belly 

A snake's belly slides right along the ground as low as any animal can get.

His reputation was lower than a snake's belly.

lower than a snake's belly by Deborah Lee June 11, 2006