- the imaginary, invisible wall, as across the front of a stage, that separates the world constructed by a play, movie, television show, video game, or literary work from the actual world inhabited by the audience.
- to violate the conventional separation between the world of a play, movie, television show, video game, or literary work and the world inhabited by the viewer:The actor’s periodic asides to the audience break the fourth wall and elicit much-needed laughs.
