Plain English Meaning

Choosing to land somewhere other than where you originally planned to go, because something has changed and continuing to the original airport is no longer the right choice.

Full Definition

The act of changing course in flight to land at an airport other than the originally intended destination, typically due to weather, fuel concerns, mechanical issues, medical emergencies, or other operational factors that make continuing to the planned destination unsafe or impractical.

Context Anchor

Seen when using avionics, such as a primary flight display, to find and navigate to a nearby suitable airport during a change of plan.

Derivation

From Latin 'divertere', meaning 'to turn aside' (di- 'apart' + vertere 'to turn'). The aviation meaning keeps this sense exactly: turning aside from the planned to a different destination.