A "dive" in which you hold your knees to your chest and hit the water with your fat ass with as much force as possible with the purpose of creating a gigantic splash, thus soaking everyone in the near vicinity.
That cannonball your mother just performed strangely reminded me of the movie "Deep Impact".
by Nick D November 23, 2004
The term cannonball was first used by Carl Kearney Spackler (Bill Murray) in the masterpiece film Caddyshack. To do a cannonball you must first fill your lungs with weed smoke, while holding the smoke in you drink liquor. Preferably Johnnie Black. And take big swig not a little pussy shot. Then exhale. Say "Cannonball" and pass the bong and Johnnie black to your boy n-word Drew and repeat until liquor is finished (nobone in their right mind would ever run out of weed.) The best time for cannonballs is wednesdays at 10:30 during the Chappelle show. The best mix for this is Johnnie Black and Sour Diesel from the wiseman, Veil.
After I Kobed her I took a few cannnballs.
by Lenox February 19, 2004
A metallic, spherical object that does not hover nor float. Often shot out of a cannon.
The feather floated. Much in the way a cannonball does not.
by fiddle November 6, 2004
When a guy jerks off and shoots the load in his own face.
guy 1: Hey, I'm going to jerk off.
guy 2: OK. Don't forget your cannonball goggles.
by Kevin Dean Nicewanger April 17, 2006
When you take a bong hit of a newport 100, then pound an entire 40 oz of olde english
Man did u see that scumbag do that cannonball.
by Adam Smirti May 21, 2007
When you hold your foreskin tightly with your dominant hand, and proceed to urinate within the sealed foreskin vicinity. Wait until maximum pressure is reached, and release upon shower-mates.
Man, Nate got hit with the WORST cannonball yesterday in the locker room!
by NateDun January 24, 2009
when a male is about to ejaculate and the partner is across the room and the sperm reaches the partner causing it to fly through the air
"lay down over there so i can cannonball you"
by jankydank August 5, 2009