Before revision: Great-circle navigation or orthodromic navigation (related to orthodromic course; from the Greek ορθóς, right angle, and δρóμος, path ) is the practice of navigating a vessel (a ship or aircraft) along a great circle.
After revision: Great-circle navigation or orthodromic navigation (related to orthodromic course; ) is the practice of navigating a vessel (a ship or aircraft) along a great circle.