Synchronous orbit

Synchronous orbit: Any orbit in which an orbiting object has a period equal to the average rotational period of the body being orbited, and in the same direction of rotation as that body.

Note 1: A synchronous orbit need not be equatorial, but it usually is, ideally. A body in a nonequatorial synchronous orbit will, when observed from a fixed point on the orbited body, appear to move up and down, i.e., northward and southward. If the synchronous orbit is not perfectly circular, the orbiting body will appear to move back and forth, eastward and westward. The combination of these two motions will produce a figure-8 pattern as seen from the orbited body.

Note 2: A synchronous orbit about the Earth that is circular and lies in the equatorial plane is called a geostationary orbit.

Source: from Federal Standard 1037C