To leave somewhere (normally a party or bar) without the knowledge of those in attendance. Usually after drinking way too much and in need of sleep or food, however a hoffa can be performed for any reason (i.e. to hook up). Performed usually to avoid unwanted opinions from friends in attendance.
Person 1: Dude, that guy has been making out with that chick for the last five minutes. I would have sworn he was gay!
Person 2: Yeah, he's definitely gay. Just look at him.
Person 1: Oh, he must be doing the Hoffa.
jimmy hoffa was the union leader who mysteriously vanished. his body is still nowhere to be found. people say he was killed by the mafia but its still a big mystery.