1) Celestial point 2) Point of periapsis 1) Perigee 2) Perihelion 3) Perilune 4) Periselene 5) Perijove 
is the point of closest approach between two orbiting objects.
That point in an orbit which is nearest to the primary.
The point in an orbit when two objects are closest together. Special names are given to this point for commonly used systems, including periastron, perihelion, and perigee. Compare with apoapsis.
the point in the orbit of a satellite or planet which is at a minimum distance from the centre of mass of the primary body
The point in the orbit closest to the planet.
The point in an orbit closest to a body other than the Sun or the Earth.
The point in an orbit closest to the body being orbited. 
The point in the orbit closest to the planet.
[n] - (astronomy) the point in as orbit closest to the body being orbited
periapsis The point in an orbit that is nearest to the body being orbited or to the center of gravitational attraction.
The point of an orbit nearest to the center of attraction of an orbiting body. See also: Orbit, Pericentre, Perigee.
point of periapsis noun (astronomy) the point in as orbit closest to the body being orbited