To empty out (of some place) in great numbers and all at once. Thousands have been thronging out of the city to escape the oncoming hurricane. The final bell of the school year rang, and hundreds of students thronged out to a summer of freedom.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
throng out (of something)
[for a crowd] to swarm out of something or some place. The people thronged out of the concert hall at the end of the program. At half past ten, the crowd thronged out.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.