Something that is so utterly good that it is, as the kids say "smacking." The "ball" portion of the word denotes the presence of an object or person in which it "smacks."
Kyle: "Yo did you try that Kush Mints yet? I had to buy more it was so good, that shit is Smackball on god"
by 2G Quigg November 13, 2021
A lazy heroin addict, one who does nothing except smack all day and is smacked out all the time without exception
Hey what's olde boy doing these days, you think he wants to go to the concert?
-what? him? he's a smackball, he never leaves the house or does anything except nod out-
-what? him? he's a smackball, he never leaves the house or does anything except nod out-
by Comrade Plasternasty August 29, 2008