apsis — English Dictionary

Noun

1. A recess or projection, with a dome or vault, at the east end of a church.

   Synonyms

   apseapside

   Examples

   More examples (1)

   Like Henry's collegiate church […] the cathedral is a cruciform basilica of the double bay system with four square bays in the central nave, western transoms, a quadrum for the choir, an apsis, and a transept with auxiliary apses.

2. 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.

   Synonyms

   apseapside

Noun

1. a domed or vaulted recess or projection on a building especially the east end of a church; usually contains the altar

   Synonyms

   apse

   Broader terms

   recessniche