Which term describes a moment of sudden revelation in a literary work?

The term that describes a moment of sudden revelation in a literary work is "epiphany." This term is often used in literature to indicate a moment where a character gains profound insight or a new understanding about themselves, the world, or their situation. This transformative experience can lead to significant changes in a character's thoughts or actions and is pivotal in the development of the narrative.

In contrast, the climax refers to the point of highest tension in a story, where the main conflict reaches its peak. The denouement follows the climax and serves as the resolution of the plot, wrapping up loose ends and revealing the outcomes for the characters. Crescendo, on the other hand, is a term originally from music and describes a gradual increase in loudness, which isn't directly applicable to the sudden insight characteristic of an epiphany. Therefore, "epiphany" stands out as the most fitting term to describe this moment of revelation in literature.