Originally Posted by
Bostondevil
In theater jargon, a "pick up" is a rehearsal scheduled after a show opens to address any issues that have arisen or, in the case of a long run, to provide the director with a chance to give notes/make changes/check in on how the show it going.
In the movies, sometimes after a film has wrapped, the editing process reveals the need for footage/scenes that were not part of the original shoot. When these scenes are filmed, they are called "pick ups", actor contracts usually have clauses that require them to make themselves available for pick ups.