What is the shortest distance between two points on the Earth's globe called?

The shortest distance between two points on the Earth's globe is known as a great circle. A great circle is defined as the largest circle that can be drawn on a sphere, resulting from the intersection of the sphere with a plane that passes through its center. Because the Earth is approximately spherical, if you were to draw a circle that passes through both points and the center of the Earth, that circle would be a great circle.

When traveling long distances, aircraft and ships typically follow great circle routes to minimize distance, which translates to conserving fuel and time. This concept is essential in navigation and is why you often see flight paths curve on two-dimensional maps; these are, in fact, straight paths in three-dimensional space along the curvature of the Earth.

The other options do not accurately describe this shortest distance. "Direct route" and "shortest path" are more vague and not specifically defined in geodesic terms, while "the straight line" disregards the three-dimensional aspect of Earth’s topography, failing to account for its curvature. Thus, great circles represent the true shortest paths over the Earth's surface.