MEO 【Intermediate Circular Orbit】
full spelling ： Medium Earth Orbit
Medium Earth Orbit is refers to an altitude below 35,786 km (geostationary orbit) and above the altitude of Low Earth Orbit (LEO). Medium Earth Orbit enables a satellite provider to cover the earth with fewer satellites than Low Earth Orbit, but requires more satellites to do so than geostationary orbit.
The most common use for satellites in this region is for navigation, such as the GPS and Glonass constellations (Russian counterpart to the United States GPS system).