Definition of "apse" []

• Architecture A usually semicircular or polygonal, often vaulted recess, especially the termination of the sanctuary end of a church. (noun)
• Astronomy An apsis. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The term apse was first used in reference to a Roman basilica, of which it was a characteristic feature."
• "The central apse is rectangular and heavy, the little southern apse is short and round, and that of the north is tall and thin as a pepper-box."
• "Preceding the apse was a bema, or altar podium, measuring 5.63 meters."