The act of thrusting the man junk so far into a woman's (or man's if you are homosexual) anus multiple times that the balls consistently slap against the "host's" butt cheeks making a sound like a great high five.
KirtKanReed: "i am soo hungover bro, i can't remember anything about last night."

ChadKant: "you wouldn't want to."

Zenovia's Playa: " YEAH! BECAUSE CHAD GAVE YOU THE sack whack on the back crack WHILE YOU WERE SHIT FACED DRUNK LAST NIGHT AND PASSED OUT ON THE COUCH!"
by Zenovia's Playa June 14, 2009
Get the Sack Whack on the Back Crack mug.
When you have a small butt and it looks like your butt is part of your back. The only butt feature is the crack.
"Yo he gots no butt, das a back and crack!"
by sk8erboihfm March 6, 2009
Get the back and crack mug.
1. (noun) The white or gray film that forms on the inside of a glass dick after smoking crystal meth.

2. (verb) The act of "melting" the aforementioned film off of the glass dick while inhaling the resulting smoke in an attempt to get high after you've smoked all your d.

3. (verb) The action and reaction of recrystalization of crystal meth when melted completely and then cooled.
Look at all the crack back on the inside of this pipe! Someone must have smoked a teener to their dome.

My roomate smoked the rest of my shabs and now I'm stuck cracking back!

I can't believe this shit is good! It's actually cracked back!
by Shabarella June 29, 2005
Get the crack back mug.
someone so skinny their ass is nothin' stickin' out past their butt...
shoot, girl, you gotta eat somethin' you got nothin' but a back with a crack!
by deja2entendu May 4, 2006
Get the back with a crack mug.
used to refer to women who have very flat asses. their lack of an ass makes it appear as though they just have a butt crack on their backs.
that skinny chick has a crack back.
by mr.pubes February 4, 2006
Get the crack back mug.
A humpback (someone with a large hump on their back)who is either on crack or sells crack. They are most commonly found on street corners and in dark alleys. Almost every town has their own crack-back who supplys them with crack and/or a good laugh, because a guy with a big hump on his back is fuckin funny.
Erik- Dude, wanna go pwn those noobs jamie and heather in foosball again?
Jake- Hell yeah... but lets crackalax for an hour or so before we go
Erik- Aight. But where are we gonna get the crack mayne?
Jake- Don't worry i know this crack-back who is always hangin out behind taco bell... we can score some off him
Erik- Word.
by Wlnga September 24, 2006
Get the Crack-Back mug.
(v.) Feeling tore up, exhausted.
(adv.)Not caring about your appearance to others or yourself.
(adj.)Being so high off of dope that your eyelids are peeled back into your face.
That lady looks like she hasn't slept or bathed in a month. She looks cracked back! Go holla at her, G.
by greg gonzalez April 3, 2008
Get the cracked back mug.