The title of this article is conjectural. Though the topic is found within The Simpsons universe, a proper name is not available.
The Circus Line couch gag is the ninth couch gag of Season 4. It is the first elongated couch gag made for The Simpsons, and the most often used gag in the show.
The Simpsons get up off the couch and form a line with some dancers. The wall behind the couch moves away. This reveals a lot of other circus acts such as elephants, jugglers, magicians, trapeze artists and Santa's Little Helper walking on two legs.