Found 2 items, similar to Apsis.
English → English (WordNet) Definition: apsis apsis n : a domed or vaulted recess or projection on a building especially the east end of a church; usually contains the altar [syn: apse] [also: apsides (pl)]
English → English (gcide) Definition: Apsis Apsis \Ap"sis\ ([a^]p"s[i^]s), n.; pl. Apsides ([a^]p"s[i^]*d[=e]z). See Apse. [L. apsis, absis, Gr. "apsi`s, "apsi^dos, a tying, fastening, the hoop of a wheel, the wheel, a bow, arch, vault, fr. "a`ptein to fasten.] 1. (Astron.) One of the two points of an orbit, as of a planet or satellite, which are at the greatest and least distance from the central body, corresponding to the aphelion and perihelion of a planet, or to the apogee and perigee of the moon. The more distant is called the higher apsis; the other, the lower apsis; and the line joining them, the line of apsides. [1913 Webster] 2. (Math.) In a curve referred to polar co["o]rdinates, any point for which the radius vector is a maximum or minimum. [1913 Webster] 3. (Arch.) Same as Apse. [1913 Webster]