'periapsis' originates from Greek, specifically the elements 'peri-' and 'apsis', where 'peri-' meant 'around' and 'apsis' meant 'arch' or 'vault' (used for 'arch' or 'loop').

'periapsis' was formed in modern scientific (New Latin/Modern Greek-rooted) terminology from the Greek elements and entered English via New Latin; the plural form 'periapsides' follows the Greek plural pattern and is used in technical contexts.

Initially, it meant 'the point of closest approach in an orbit', and over time it has retained this technical meaning in astronomy and orbital mechanics.