The highest point.
The point, in any trajectory of an object in space, where it is farthest from the Earth.
The point, in an orbit about the Earth, that is farthest from the Earth: the apoapsis of an Earth orbiter.
The point, in an orbit about any planet, that is farthest from the planet: the apoapsis of any satellite.
Highest point or state; peak.
The point in the sky vertically above a given position or observer; the point in the celestial sphere opposite the nadir.
The highest point in the sky reached by a celestial body.