A theatrical movie, usually a major blockbuster, that runs past it's designated release season (i.e. summer releases playing into fall, holiday movies in January or later, etc.) to the point where only a few theaters are showing them anymore, and there are usually less than ten people in the audience, and chances are most of them already saw it during it's initial release period.
Jane: Hey you wanna catch that new superhero flick this weekend?
Bob: I don't know, the theaters will be awfully crowded since it'll be just coming out. Let's wait a month or so until it becomes a lame duck film.