(Parece gíria, mas não é!)
Houaiss: "a multidão vazou pelo portão"
ir para fora de, sair, escapar(-se)
Definition: A mildly offensive way to tell someone to leave a place.
E.g.1: "Pick up that rubbish!" shouted the bad-tempered old lady "And now buzz off!"
E.g.2: We won't stay too long. We'll buzz off at midday.
This phrasal verb cannot be separated.
Fonte: Knights' English / Houaiss