great circle

noun2

1. •
   A circle defined as the intersection of the surface of a sphere and a plane which passes through the centre of the sphere.
2. •
   A segment of such circle representing the shortest distance between two points on the surface of a sphere.

   • Wherever a navigator may be, it certainly would be to his advantage to be able to find the great circle, or shortest course, and the distance, to his port of destination, [....] — 1902