What defines a nonstop flight?

A nonstop flight is defined as a flight that travels from the departure airport to the destination airport without making any intermediate stops. This means that passengers board the plane at one location and remain on the same aircraft until they arrive at their intended destination. The key characteristic of a nonstop flight is its direct route, allowing for a quicker and more convenient travel experience compared to flights that require layovers or connections. In this context, the other options do not meet the criteria for a nonstop flight, as they involve additional stops or interruptions in the journey.