Definition

A curved line or trajectory; in storytelling, a narrative arc is the overall shape and progression of a plot. More generally, any curved path or the span of time over which something develops.

Example Usage

The arc of the story takes the hero from innocence to wisdom.

Origin

From Latin 'arcus' meaning bow or arch; used in geometry for centuries before being adopted as literary terminology.

Fun Fact

The concept of 'story arc' is often visualized as a mountain shape (rising action, climax, falling action), which itself is an arc.

Source: Definition backfill (hailey)