As nouns the difference between periapsis and periapses
is that periapsis is the point of a body's elliptical orbit about the system's centre of mass where the distance between the body and the centre of mass is at its minimum while periapses is plural of lang=en.
periapsis
English
Noun
(periapsides)
(astronomy) The point of a body's elliptical orbit about the system's centre of mass where the distance between the body and the centre of mass is at its minimum.
Usage notes
In the case of some particular celestial bodies, specialised terms are used.
Antonyms
* apoapsis
Synonyms
* pericenter
Related terms
* periastron
* perihelion
* perilune
* perigee
See also
* (Apsis)