apsis
演变路径（由近及远）
词源说明
From Latin apsis, hapsis, from Ancient Greek ἁψίς (hapsís, “arch, vault”). See also apse.
释义（英文）
名词 Noun
- (architecture) A recess or projection, with a dome or vault, at the east end of a church.
- (astronomy) Either of the points in the elliptical orbit of a planet, comet, or moon where it is closest or furthest from the body it orbits; examples are perihelion, aphelion, perigee, and apogee