initial great-circle course

initial great-circle course

[i′nish·əl ′grāt ‚sər·kəl ‚kȯrs] (navigation) The direction, at the point of departure, of the great circle through that point and the destination, expressed as the angular distance from a reference direction, usually north, to that part of the great circle extending toward the destination. Also known as initial great-circle direction.