Apse

Semicircular or polyhedral construction at the end of the chancel, containing the altar and sanctuary, and roofed with a half dome. The apse was a standard feature of the architecture of the early church.

Glossary definitions provided courtesy of Church Publishing Incorporated, New York, NY,(All Rights reserved) from "An Episcopal Dictionary of the Church, A User Friendly Reference for Episcopalians," Don S. Armentrout and Robert Boak Slocum, editors.