periapsis
|pe-ri-ap-sis|
🇺🇸
/ˌpɛriˈæpsɪs/
🇬🇧
/ˌpɛrɪˈæpsɪs/
closest point in an orbit
Etymology
'periapsis' originates from Greek elements via Modern Latin/astronomical usage: 'peri-' from Greek 'peri-' meaning 'around' and 'apsis' from Greek 'apsis' meaning 'arch' or 'loop' (used in astronomy for the points of an orbit).
'periapsis' was formed in scientific/astronomical Latin by combining the Greek prefix 'peri-' with 'apsis' and was adopted into English usage in the 19th–20th centuries as a technical term in celestial mechanics.
Initially the components referred more generally to 'around an arch/loop'; over time the compound specialized to mean 'the point in an orbit closest to the central body'.
Meanings by Part of Speech
Noun 1
the point in an orbit at which a satellite or celestial body is closest to the body it is orbiting (general term; specific bodies have special names, e.g. perigee for Earth, perihelion for the Sun).
The spacecraft reached periapsis before initiating the engine burn.
Synonyms
Antonyms
Last updated: 2025/12/02 10:45