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n.; pl. Apses [ See Apsis. ] 1. (Arch.) (a) A projecting part of a building, esp. of a church, having in the plan a polygonal or semicircular termination, and, most often, projecting from the east end. In early churches the Eastern apse was occupied by seats for the bishop and clergy. Hence: (b) The bishop's seat or throne, in ancient churches. [ 1913 Webster ]

2. A reliquary, or case in which the relics of saints were kept. [ 1913 Webster ]

☞ This word is also written apsis and absis. [ 1913 Webster ]