diegesis

Noun C1 – Advanced

The narrated world of a story, meaning everything that the characters within it can perceive or experience.

"A song playing on a character's car radio belongs to the diegesis, but the film's background score does not."

This term is mostly used in film studies, to separate sound or events inside the story's world (diegetic) from those added only for the audience (non-diegetic).