Also found in: Dictionary.
To arrive (at or to something) in a very casual manner, especially when one is late. That's the last time I invited Jeff to a dinner party—we were nearly finished with the main course by the time he decided to rock up. I don't think it matters what time we rock up, so let's not rush.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.