(noun) A large shit, that when shat, feels like you are passing a 9-ball from your ass. A 9-ball takes an extraordinary amount of force to pass.
Common injuries that occur from dropping a 9-ball include but are not limited to: sphincter tears, busted blood vessels in the eyes, hernias, bloody nose, and in rare cases death.
GUY 1: "Hey man, where've ya been? Your wings are cold."
GUY 2: "I had to drop a 9-ball!"
GUY 1: "Well that explains the limp and the blood."
(noun) A specific type of shit. One that the earth's gravitational pull is exerting an unusual amount of force upon. A heavy, when shat, will make a very discernible low-pitched plop in the can
"Dude, I simply cannot finish eating this 12th can of baked beans until I go drop a heavy!"