From Longman Dictionary of Contemporary Englishapseapse /æps/ noun [countable] technical TBBthe curved inside end of a building, especially the east end of a church
Examples from the Corpus
apse• It is surrounded by buildings, the houses being built on to it at the eastern apse.• Standing in the huge apse, covered by a baldacchino, was the monument to Peter.• At the east end is a rectangular choir and later apse.• The tall apse windows give better illumination to the east end.• These towers were transeptal or set just behind the apses and were polygonal or circular in form.• The apse mosaics have a gold background and are of early type, being stiff and formal in design.• The western apse is of about the year 1000 and the narthex is later.• Later designs further adapted the basilican plan with apses at both east and west ends and sometimes added short transepts.Origin apse (1800-1900) Latin apsis 