diegetic (diegesis)

Diegetic, or diegesis, simply means realistic or logically existing, such as the music that plays on a character's radio in a scene. More generally, diabetic refers to the narrative elements of a film (such as spoken dialogue, other sounds, action) that appear in, are shown, or naturally originate within the content of the film frame. The opposite is "non-diegetic" elements, such as sounds (e.g., background music, the musical score, a voice-over, or other sounds) without an origin within the film frame itself. In an objective shot, the most common camera shot, it simply presents what is before the camera in the diegesis of the narrative.