The act of being incredibly lazy, as in lying around like a sack of potatoes. One who sacks is often seen lounging on their couch all day playing video games and watching movies.
Jim: "Yo have you seen Alec today?"
Mike: "Not yet. Did you check his apartment? Bet you he's sacking on the couch."
Mike: "Not yet. Did you check his apartment? Bet you he's sacking on the couch."
by BroBro23 February 28, 2018
